Basic Usage

The spack command has many subcommands. You’ll only need a small subset of them for typical usage.

Note that Spack colorizes output. less -R should be used with Spack to maintain this colorization. E.g.:

$ spack find | less -R

It is recommended that the following be put in your .bashrc file:

alias less='less -R'

Listing available packages

To install software with Spack, you need to know what software is available. You can see a list of available package names at the Package List webpage, or using the spack list command.

spack list

The spack list command prints out a list of all of the packages Spack can install:

$ spack list
abinit                           llvm-lld                               py-xmlrunner
abyss                            llvm-openmp-ompt                       py-xopen
ack                              lmdb                                   py-xpyb
activeharmony                    lmod                                   py-xvfbwrapper
adept-utils                      lndir                                  py-yapf
adios                            log4cxx                                py-yt
adios2                           lrslib                                 py-zmq
adlbx                            lrzip                                  python
adol-c                           lua                                    qbank
albert                           lua-bitlib                             qbox
alglib                           lua-jit                                qhull
allinea-forge                    lua-lpeg                               qmd-progress
allinea-reports                  lua-luafilesystem                      qrupdate
allpaths-lg                      lua-luaposix                           qt
alquimia                         lua-mpack                              qt-creator
alsa-lib                         luit                                   qtgraph
amg2013                          lulesh                                 qthreads
ampliconnoise                    lwgrp                                  quinoa
amr-exp-parabolic                lwm2                                   qwt
amrex                            lz4                                    r
andi                             lzma                                   r-abind
angsd                            lzo                                    r-ada
ant                              m4                                     r-adabag
antlr                            mad-numdiff                            r-ade4
ape                              mafft                                  r-adegenet
apex                             magics                                 r-affyio
applewmproto                     magma                                  r-ape
appres                           makedepend                             r-assertthat
apr                              mallocmc                               r-base64enc
apr-util                         man-db                                 r-bh
archer                           mariadb                                r-biobase
argtable                         matio                                  r-biocgenerics
armadillo                        matlab                                 r-biocinstaller
arpack-ng                        maven                                  r-bit
asciidoc                         maverick                               r-bitops
aspa                             mawk                                   r-boot
astra                            mbedtls                                r-brew
astral                           mcl                                    r-c50
astyle                           mdtest                                 r-car
atk                              meep                                   r-caret
atlas                            memaxes                                r-catools
atompaw                          meme                                   r-checkpoint
atop                             mercurial                              r-chron
augustus                         mesa                                   r-class
autoconf                         mesa-glu                               r-cluster
autogen                          meshkit                                r-coda
automaded                        meson                                  r-codetools
automake                         mesquite                               r-coin
bamtools                         metis                                  r-colorspace
bamutil                          mfem                                   r-corpcor
bash                             microbiomeutil                         r-corrplot
bash-completion                  miniaero                               r-crayon
bats                             miniamr                                r-cubature
bazel                            miniconda2                             r-cubist
bbcp                             miniconda3                             r-curl
bbmap                            minife                                 r-data-table
bcftools                         minighost                              r-dbi
bcl2fastq2                       minigmg                                r-deldir
bdftopcf                         minimd                                 r-dendextend
bdw-gc                           minismac2d                             r-deoptim
bear                             minixyce                               r-deoptimr
beast2                           mirdeep                                r-devtools
bedtools2                        mitofates                              r-diagrammer
beforelight                      mitos                                  r-dichromat
benchmark                        mkfontdir                              r-digest
berkeley-db                      mkfontscale                            r-diptest
bertini                          mlhka                                  r-domc
bib2xhtml                        moab                                   r-doparallel
bigreqsproto                     molcas                                 r-dplyr
binutils                         mono                                   r-dt
bioawk                           mosh                                   r-dygraphs
bison                            mothur                                 r-e1071
bitmap                           mozjs                                  r-ellipse
blast-plus                       mpc                                    r-ergm
blat                             mpe2                                   r-evaluate
blaze                            mpest                                  r-expm
bliss                            mpfr                                   r-factoextra
blitz                            mpibash                                r-factominer
bml                              mpiblast                               r-filehash
boost                            mpich                                  r-flashclust
boostmplcartesianproduct         mpifileutils                           r-flexmix
bowtie                           mpileaks                               r-foreach
bowtie2                          mpip                                   r-foreign
boxlib                           mpir                                   r-formatr
bpp-core                         mpix-launch-swift                      r-formula
bpp-phyl                         mrbayes                                r-fpc
bpp-seq                          mrnet                                  r-gdata
bpp-suite                        msgpack-c                              r-geosphere
braker                           multiverso                             r-ggmap
brigand                          mummer                                 r-ggplot2
bsseeker2                        mumps                                  r-ggpubr
bucky                            munge                                  r-ggrepel
busco                            muparser                               r-ggsci
butter                           muscle                                 r-ggvis
bwa                              muse                                   r-gistr
bzip2                            muster                                 r-git2r
c-blosc                          mvapich2                               r-glmnet
caffe                            mxml                                   r-gmodels
cairo                            nag                                    r-gmp
caliper                          nalu                                   r-googlevis
callpath                         namd                                   r-gridbase
cantera                          nano                                   r-gridextra
canu                             nanoflann                              r-gtable
cap3                             nasm                                   r-gtools
cares                            nauty                                  r-hexbin
cask                             nccl                                   r-highr
catch                            nccmp                                  r-htmltools
cbench                           ncdu                                   r-htmlwidgets
cblas                            ncftp                                  r-httpuv
cbtf                             ncl                                    r-httr
cbtf-argonavis                   nco                                    r-igraph
cbtf-argonavis-gui               ncurses                                r-influencer
cbtf-krell                       ncview                                 r-inline
cbtf-lanl                        ndiff                                  r-ipred
ccache                           nekbone                                r-irdisplay
cctools                          neovim                                 r-irkernel
cdbfasta                         netcdf                                 r-irlba
cdd                              netcdf-cxx                             r-iterators
cddlib                           netcdf-cxx4                            r-jpeg
cdhit                            netcdf-fortran                         r-jsonlite
cdo                              netgauge                               r-kernlab
cereal                           netgen                                 r-kernsmooth
cfitsio                          netlib-lapack                          r-kknn
cgal                             netlib-scalapack                       r-knitr
cgm                              nettle                                 r-labeling
cgns                             nextflow                               r-laplacesdemon
charm                            nfft                                   r-lattice
check                            nginx                                  r-lava
chlorop                          ngmlr                                  r-lazyeval
chombo                           ninja                                  r-leaflet
cityhash                         ninja-fortran                          r-leaps
clamr                            nmap                                   r-learnbayes
cleaveland4                      node-js                                r-lme4
cleverleaf                       notmuch                                r-lmtest
clfft                            npb                                    r-lpsolve
clhep                            npm                                    r-lubridate
cloog                            npth                                   r-magic
cloverleaf                       nspr                                   r-magrittr
cloverleaf3d                     numactl                                r-mapproj
clustalo                         numdiff                                r-maps
clustalw                         nut                                    r-maptools
cmake                            nwchem                                 r-markdown
cmocka                           ocaml                                  r-mass
cmor                             oce                                    r-matrix
cnmem                            oclock                                 r-matrixmodels
cnpy                             octave                                 r-mclust
cns-nospec                       octave-splines                         r-mda
cntk                             octopus                                r-memoise
cntk1bitsgd                      of-adios-write                         r-mgcv
codar-cheetah                    ompss                                  r-mime
cohmm                            ompt-openmp                            r-minqa
coinhsl                          oniguruma                              r-mlbench
comd                             ont-albacore                           r-modelmetrics
compiz                           opari2                                 r-modeltools
compositeproto                   openbabel                              r-mpm
conduit                          openblas                               r-multcomp
constype                         opencoarrays                           r-munsell
converge                         opencv                                 r-mvtnorm
coreutils                        openexr                                r-ncdf4
corset                           openfoam-com                           r-network
cosmomc                          openfoam-org                           r-networkd3
cosp2                            openfst                                r-nlme
cp2k                             openjpeg                               r-nloptr
cppad                            openmc                                 r-nmf
cppcheck                         openmpi                                r-nnet
cpprestsdk                       openscenegraph                         r-np
cppunit                          openspeedshop                          r-numderiv
cppzmq                           openssh                                r-openssl
cram                             openssl                                r-packrat
cryptopp                         opium                                  r-pacman
cscope                           opus                                   r-party
csdp                             orfm                                   r-partykit
cub                              orthomcl                               r-pbdzmq
cube                             osu-micro-benchmarks                   r-pbkrtest
cuda                             otf                                    r-permute
cuda-memtest                     otf2                                   r-pkgmaker
cudnn                            p4est                                  r-plotrix
cufflinks                        p7zip                                  r-pls
cups                             pacbio-daligner                        r-plyr
curl                             pacbio-damasker                        r-png
cvs                              pacbio-dazz-db                         r-prabclus
czmq                             pacbio-dextractor                      r-praise
dakota                           pagit                                  r-preprocesscore
daligner                         pagmo                                  r-prodlim
damageproto                      paml                                   r-proto
damselfly                        panda                                  r-pryr
darshan-runtime                  pango                                  r-quadprog
darshan-util                     papi                                   r-quantmod
dash                             paradiseo                              r-quantreg
datamash                         parallel                               r-r6
dataspaces                       parallel-netcdf                        r-randomforest
dbus                             paraver                                r-raster
dealii                           paraview                               r-rbokeh
dejagnu                          parmetis                               r-rcolorbrewer
dia                              parmgridgen                            r-rcpp
dialign-tx                       parsimonator                           r-rcppeigen
direnv                           parsplice                              r-registry
discovar                         partitionfinder                        r-repr
dmxproto                         patch                                  r-reshape2
docbook-xml                      patchelf                               r-rgl
docbook-xsl                      pathfinder                             r-rgooglemaps
dos2unix                         pax-utils                              r-rinside
double-conversion                pbmpi                                  r-rjava
doxygen                          pcma                                   r-rjson
dri2proto                        pcre                                   r-rjsonio
dri3proto                        pcre2                                  r-rmarkdown
dtcmp                            pdsh                                   r-rminer
dyninst                          pdt                                    r-rmpfr
ea-utils                         pegtl                                  r-rmpi
easybuild                        pennant                                r-rmysql
ebms                             perl                                   r-rngtools
eccodes                          perl-dbfile                            r-robustbase
editres                          perl-dbi                               r-rodbc
eigen                            perl-devel-cycle                       r-roxygen2
elemental                        perl-extutils-makemaker                r-rpart
elfutils                         perl-font-ttf                          r-rpart-plot
elk                              perl-intervaltree                      r-rpostgresql
elpa                             perl-math-cdf                          r-rsnns
emacs                            perl-module-build                      r-rsqlite
emboss                           perl-padwalker                         r-rstan
encodings                        perl-pdf-api2                          r-rstudioapi
environment-modules              perl-star-fusion                       r-rzmq
es                               perl-sub-uplevel                       r-s4vectors
esmf                             perl-term-readkey                      r-sandwich
espresso                         perl-test-exception                    r-scales
espressopp                       perl-test-memory-cycle                 r-scatterplot3d
etsf-io                          perl-uri-escape                        r-segmented
everytrace                       perl-xml-parser                        r-seqinr
everytrace-example               petsc                                  r-shiny
evieext                          pexsi                                  r-snow
exabayes                         pfft                                   r-sp
exmcutils                        pflotran                               r-sparsem
exodusii                         pgdspider                              r-spdep
exonerate                        pgi                                    r-stanheaders
expat                            phasta                                 r-statnet-common
expect                           phylip                                 r-stringi
extrae                           picard                                 r-stringr
exuberant-ctags                  pidx                                   r-strucchange
f90cache                         pigz                                   r-survey
falcon                           piranha                                r-survival
farmhash                         pixman                                 r-tarifx
fastjar                          pkg-config                             r-testit
fastmath                         pkgconf                                r-testthat
fastphase                        planck-likelihood                      r-th-data
fastqc                           plink                                  r-threejs
fastx-toolkit                    plumed                                 r-tibble
fenics                           pmgr-collective                        r-tidyr
ferret                           pmix                                   r-trimcluster
ffmpeg                           pnfft                                  r-trust
fftw                             pngwriter                              r-ttr
fimpute                          poamsa                                 r-uuid
findutils                        pocl                                   r-vcd
fio                              polymake                               r-vegan
fish                             porta                                  r-viridis
fixesproto                       portage                                r-viridislite
flac                             postgresql                             r-visnetwork
flann                            ppl                                    r-whisker
flash                            prank                                  r-withr
flecsale                         presentproto                           r-xgboost
flecsi                           preseq                                 r-xlconnect
flex                             price                                  r-xlconnectjars
flint                            primer3                                r-xlsx
fltk                             printproto                             r-xlsxjars
flux                             probconsrna                            r-xml
fmt                              proj                                   r-xtable
foam-extend                      protobuf                               r-xts
folly                            proxymngr                              r-xvector
font-adobe-100dpi                pruners-ninja                          r-yaml
font-adobe-75dpi                 psi4                                   r-zlibbioc
font-adobe-utopia-100dpi         pstreams                               r-zoo
font-adobe-utopia-75dpi          pugixml                                raft
font-adobe-utopia-type1          pumi                                   raja
font-alias                       pvm                                    randfold
font-arabic-misc                 py-3to2                                random123
font-bh-100dpi                   py-4suite-xml                          randrproto
font-bh-75dpi                    py-abipy                               ravel
font-bh-lucidatypewriter-100dpi  py-alabaster                           raxml
font-bh-lucidatypewriter-75dpi   py-apache-libcloud                     ray
font-bh-ttf                      py-apipkg                              rdp-classifier
font-bh-type1                    py-appdirs                             readline
font-bitstream-100dpi            py-appnope                             recordproto
font-bitstream-75dpi             py-apscheduler                         redundans
font-bitstream-speedo            py-argcomplete                         relion
font-bitstream-type1             py-argparse                            rempi
font-cronyx-cyrillic             py-ase                                 rename
font-cursor-misc                 py-asn1crypto                          rendercheck
font-daewoo-misc                 py-astroid                             renderproto
font-dec-misc                    py-astropy                             resourceproto
font-ibm-type1                   py-attrs                               revbayes
font-isas-misc                   py-autopep8                            rgb
font-jis-misc                    py-babel                               rhash
font-micro-misc                  py-backports-abc                       rockstar
font-misc-cyrillic               py-backports-shutil-get-terminal-size  root
font-misc-ethiopic               py-backports-ssl-match-hostname        rose
font-misc-meltho                 py-basemap                             rr
font-misc-misc                   py-beautifulsoup4                      rsbench
font-mutt-misc                   py-binwalk                             rsem
font-schumacher-misc             py-biom-format                         rstart
font-screen-cyrillic             py-biopython                           rsync
font-sony-misc                   py-bleach                              rtags
font-sun-misc                    py-blessings                           rtax
font-util                        py-bokeh                               ruby
font-winitzki-cyrillic           py-boltons                             rust
font-xfree86-type1               py-bottleneck                          rust-bindgen
fontcacheproto                   py-brian                               sabre
fontconfig                       py-brian2                              salmon
fontsproto                       py-bsddb3                              sambamba
fonttosfnt                       py-cclib                               samrai
freebayes                        py-cdat-lite                           samtools
freetype                         py-cdo                                 sas
fseq                             py-certifi                             satsuma2
fslsfonts                        py-cffi                                savanna
fstobdf                          py-chardet                             saws
funhpc                           py-click                               sbt
gapcloser                        py-colorama                            scala
gapfiller                        py-colormath                           scalasca
gasnet                           py-configparser                        scons
gaussian                         py-counter                             scorec-core
gawk                             py-coverage                            scorep
gblocks                          py-cpuinfo                             scotch
gcc                              py-cryptography                        scr
gccmakedep                       py-csvkit                              screen
gccxml                           py-current                             scripts
gconf                            py-cutadapt                            scrnsaverproto
gdal                             py-cycler                              sctk
gdb                              py-cython                              sdl2
gdbm                             py-dask                                sdl2-image
gdk-pixbuf                       py-dateutil                            sed
geant4                           py-dbf                                 seqprep
gearshifft                       py-decorator                           seqtk
gemmlowp                         py-deeptools                           serf
genemark-et                      py-dev                                 sessreg
genometools                      py-dill                                setxkbmap
geos                             py-docutils                            sga
gettext                          py-doxypy                              shapeit
gflags                           py-doxypypy                            shared-mime-info
ghostscript                      py-dryscrape                           shiny-server
ghostscript-fonts                py-dxchange                            shortstack
giflib                           py-dxfile                              showfont
git                              py-easybuild-easyblocks                sickle
git-lfs                          py-easybuild-easyconfigs               signalp
gl2ps                            py-easybuild-framework                 silo
glew                             py-edffile                             simplemoc
glib                             py-elasticsearch                       simul
glm                              py-elephant                            simulationio
global                           py-emcee                               singularity
globalarrays                     py-entrypoints                         slepc
globus-toolkit                   py-enum34                              slurm
glog                             py-epydoc                              smalt
glpk                             py-et-xmlfile                          smc
glproto                          py-execnet                             smproxy
gmake                            py-fastaindex                          snakemake
gmap-gsnap                       py-fasteners                           snap
gmime                            py-faststructure                       snap-berkeley
gmp                              py-fiscalyear                          snappy
gmsh                             py-flake8                              snbone
gnat                             py-flask                               sniffles
gnu-prolog                       py-flexx                               snptest
gnupg                            py-funcsigs                            soap2
gnuplot                          py-functools32                         soapindel
gnutls                           py-future                              soapsnp
go                               py-futures                             somatic-sniper
go-bootstrap                     py-genders                             sortmerna
gobject-introspection            py-genshi                              sowing
googletest                       py-git-review                          sox
gource                           py-git2                                spades
gperf                            py-gnuplot                             spark
gperftools                       py-griddataformats                     sparsehash
grackle                          py-guidata                             sparta
gradle                           py-guiqwt                              spdlog
grandr                           py-h5py                                spectrum-mpi
graphlib                         py-html2text                           speex
graphmap                         py-html5lib                            sph2pipe
graphviz                         py-httpbin                             spherepack
grib-api                         py-hypothesis                          spindle
groff                            py-idna                                spot
gromacs                          py-igraph                              sqlite
gsl                              py-imagesize                           squid
gtkorvo-atl                      py-iminuit                             sspace-longread
gtkorvo-cercs-env                py-importlib                           sspace-standard
gtkorvo-dill                     py-ipaddress                           sst-dumpi
gtkorvo-enet                     py-ipdb                                sst-macro
gtkplus                          py-ipykernel                           stacks
gts                              py-ipython                             staden-io-lib
guile                            py-ipython-genutils                    star
h5hut                            py-ipywidgets                          star-ccm-plus
h5part                           py-itsdangerous                        stat
h5utils                          py-jdcal                               stc
h5z-zfp                          py-jedi                                stream
hadoop                           py-jinja2                              stress
hapcut2                          py-joblib                              stringtie
haploview                        py-jpype                               structure
harfbuzz                         py-jsonschema                          sublime-text
harminv                          py-junit-xml                           subread
hdf                              py-jupyter-client                      subversion
hdf5                             py-jupyter-console                     suite-sparse
hdf5-blosc                       py-jupyter-core                        sumaclust
help2man                         py-jupyter-notebook                    sundials
hepmc                            py-keras                               superlu
heppdt                           py-latexcodec                          superlu-dist
highfive                         py-lazy                                superlu-mt
highwayhash                      py-lazyarray                           swarm
hmmer                            py-libconf                             swiftsim
hoomd-blue                       py-line-profiler                       swig
hpccg                            py-lit                                 symengine
hpctoolkit                       py-lmfit                               sympol
hpctoolkit-externals             py-lockfile                            sz
hpl                              py-logilab-common                      tabix
hpx                              py-lxml                                talloc
hpx5                             py-lzstring                            tar
hsakmt                           py-macholib                            targetp
hstr                             py-machotools                          task
htop                             py-macs2                               taskd
htslib                           py-mako                                tau
httpie                           py-markdown                            tcl
hub                              py-markupsafe                          tcoffee
hunspell                         py-matplotlib                          tealeaf
hwloc                            py-mccabe                              tetgen
hybpiper                         py-mdanalysis                          tethex
hydra                            py-meep                                texinfo
hypre                            py-memory-profiler                     texlive
ibmisc                           py-methylcode                          the-platinum-searcher
iceauth                          py-misopy                              the-silver-searcher
icedtea                          py-mistune                             thrift
icet                             py-mock                                tig
ico                              py-mongo                               tinyxml
icu4c                            py-monotonic                           tinyxml2
id3lib                           py-monty                               tk
idba                             py-mpi4py                              tmalign
igraph                           py-mpmath                              tmhmm
ilmbase                          py-multiprocess                        tmux
image-magick                     py-multiqc                             tmuxinator
imake                            py-mx                                  tophat
impute2                          py-myhdl                               tppred
infernal                         py-mysqldb1                            transabyss
inputproto                       py-nbconvert                           transdecoder
intel                            py-nbformat                            transposome
intel-daal                       py-neo                                 transset
intel-gpu-tools                  py-nestle                              trapproto
intel-ipp                        py-netcdf4                             tree
intel-mkl                        py-netifaces                           triangle
intel-mpi                        py-networkx                            trilinos
intel-parallel-studio            py-nose                                trimgalore
intel-tbb                        py-nosexcover                          trimmomatic
intltool                         py-numexpr                             turbine
ior                              py-numpy                               turbomole
iozone                           py-numpydoc                            tut
ipopt                            py-olefile                             twm
isaac                            py-ont-fast5-api                       uberftp
isaac-server                     py-openpyxl                            udunits2
isl                              py-ordereddict                         uncrustify
itstool                          py-oset                                unibilium
itsx                             py-packaging                           unison
jags                             py-palettable                          units
jansson                          py-pandas                              unixodbc
jasper                           py-paramiko                            usearch
jdk                              py-pathlib2                            util-linux
jemalloc                         py-pathos                              util-macros
jmol                             py-pathspec                            uuid
jq                               py-patsy                               valgrind
json-c                           py-pbr                                 vampirtrace
jsoncpp                          py-periodictable                       varscan
judy                             py-petsc4py                            vc
julia                            py-pexpect                             vcftools
kahip                            py-phonopy                             vcsh
kaldi                            py-pickleshare                         vdt
kallisto                         py-pil                                 vecgeom
kbproto                          py-pillow                              veclibfort
kdiff3                           py-pip                                 vegas2
kealib                           py-pipits                              velvet
kentutils                        py-pkgconfig                           videoproto
kmergenie                        py-ply                                 viennarna
kokkos                           py-pmw                                 viewres
kripke                           py-pox                                 vim
lammps                           py-ppft                                virtualgl
last                             py-prettytable                         visit
latte                            py-proj                                vizglow
launchmon                        py-prompt-toolkit                      vmatch
lbann                            py-protobuf                            voropp
lbxproxy                         py-psutil                              votca-csg
lcals                            py-ptyprocess                          votca-ctp
lcms                             py-pudb                                votca-moo
ldc                              py-py                                  votca-tools
ldc-bootstrap                    py-py2bit                              votca-xtp
legion                           py-py2cairo                            vpfft
leveldb                          py-py2neo                              vpic
lftp                             py-py4j                                vsearch
libaec                           py-pyasn1                              vtk
libaio                           py-pybigwig                            wannier90
libapplewm                       py-pybind11                            wget
libarchive                       py-pybtex                              windowswmproto
libassuan                        py-pybtex-docutils                     wt
libatomic-ops                    py-pychecker                           wx
libbeagle                        py-pycodestyle                         wxpropgrid
libbsd                           py-pycparser                           x11perf
libbson                          py-pycrypto                            xapian-core
libcanberra                      py-pycurl                              xauth
libcap                           py-pydatalog                           xbacklight
libcerf                          py-pydispatcher                        xbiff
libcircle                        py-pydot                               xbitmaps
libconfig                        py-pyelftools                          xcalc
libctl                           py-pyfasta                             xcb-demo
libdivsufsort                    py-pyfftw                              xcb-proto
libdmx                           py-pyflakes                            xcb-util
libdrm                           py-pygments                            xcb-util-cursor
libdwarf                         py-pygobject                           xcb-util-errors
libedit                          py-pygtk                               xcb-util-image
libelf                           py-pylint                              xcb-util-keysyms
libemos                          py-pymatgen                            xcb-util-renderutil
libepoxy                         py-pyminifier                          xcb-util-wm
libevent                         py-pympler                             xclipboard
libevpath                        py-pynn                                xclock
libfabric                        py-pypar                               xcmiscproto
libffi                           py-pyparsing                           xcmsdb
libffs                           py-pypeflow                            xcompmgr
libfontenc                       py-pyprof2html                         xconsole
libfs                            py-pyqt                                xcursor-themes
libgcrypt                        py-pyrad                               xcursorgen
libgd                            py-pysam                               xdbedizzy
libgit2                          py-pyscaf                              xditview
libgpg-error                     py-pyserial                            xdm
libgpuarray                      py-pyside                              xdpyinfo
libgtextutils                    py-pysocks                             xdriinfo
libharu                          py-pytables                            xedit
libhio                           py-pytest                              xerces-c
libice                           py-pytest-cov                          xev
libiconv                         py-pytest-flake8                       xextproto
libint                           py-pytest-httpbin                      xeyes
libjpeg                          py-pytest-mock                         xf86bigfontproto
libjpeg-turbo                    py-pytest-runner                       xf86dga
libksba                          py-pytest-xdist                        xf86dgaproto
liblbxutil                       py-python-daemon                       xf86driproto
libmatheval                      py-python-gitlab                       xf86miscproto
libmesh                          py-pythonqwt                           xf86rushproto
libmng                           py-pytz                                xf86vidmodeproto
libmongoc                        py-pywavelets                          xfd
libmonitor                       py-pyyaml                              xfindproxy
libnbc                           py-qtawesome                           xfontsel
libogg                           py-qtconsole                           xfs
liboldx                          py-qtpy                                xfsinfo
libpciaccess                     py-quantities                          xfwp
libpfm4                          py-radical-utils                       xgamma
libpipeline                      py-ranger                              xgc
libpng                           py-readme-renderer                     xhost
libpsl                           py-regex                               xineramaproto
libpthread-stubs                 py-requests                            xinit
libquo                           py-restview                            xinput
libsigsegv                       py-rope                                xkbcomp
libsm                            py-rpy2                                xkbdata
libsodium                        py-rsa                                 xkbevd
libspatialindex                  py-rtree                               xkbprint
libsplash                        py-saga-python                         xkbutils
libssh2                          py-scientificpython                    xkeyboard-config
libsvm                           py-scikit-image                        xkill
libszip                          py-scikit-learn                        xload
libtermkey                       py-scipy                               xlogo
libtiff                          py-seaborn                             xlsatoms
libtool                          py-setuptools                          xlsclients
libunistring                     py-sh                                  xlsfonts
libunwind                        py-shiboken                            xmag
libuuid                          py-simplegeneric                       xman
libuv                            py-simplejson                          xmessage
libvorbis                        py-singledispatch                      xmh
libvterm                         py-sip                                 xmlto
libwebsockets                    py-six                                 xmodmap
libwindowswm                     py-slepc4py                            xmore
libx11                           py-sncosmo                             xorg-cf-files
libxau                           py-snowballstemmer                     xorg-docs
libxaw                           py-spectra                             xorg-gtest
libxaw3d                         py-spefile                             xorg-server
libxc                            py-spglib                              xorg-sgml-doctools
libxcb                           py-sphinx                              xphelloworld
libxcomposite                    py-sphinx-bootstrap-theme              xplor-nih
libxcursor                       py-sphinx-rtd-theme                    xplsprinters
libxdamage                       py-sphinxcontrib-bibtex                xpr
libxdmcp                         py-sphinxcontrib-programoutput         xprehashprinterlist
libxevie                         py-sphinxcontrib-websupport            xprop
libxext                          py-spyder                              xproto
libxfixes                        py-spykeutils                          xproxymanagementprotocol
libxfont                         py-sqlalchemy                          xqilla
libxfont2                        py-statsmodels                         xrandr
libxfontcache                    py-storm                               xrdb
libxft                           py-subprocess32                        xrefresh
libxi                            py-symengine                           xrootd
libxinerama                      py-symfit                              xrx
libxkbfile                       py-sympy                               xsbench
libxkbui                         py-tabulate                            xscope
libxml2                          py-tappy                               xsdk
libxmu                           py-terminado                           xsdktrilinos
libxp                            py-theano                              xset
libxpm                           py-tifffile                            xsetmode
libxpresent                      py-tomopy                              xsetpointer
libxprintapputil                 py-tornado                             xsetroot
libxprintutil                    py-tqdm                                xsm
libxrandr                        py-traitlets                           xstdcmap
libxrender                       py-tuiview                             xterm
libxres                          py-twisted                             xtrans
libxscrnsaver                    py-typing                              xtrap
libxshmfence                     py-tzlocal                             xts
libxslt                          py-unittest2                           xvidtune
libxsmm                          py-unittest2py3k                       xvinfo
libxstream                       py-urllib3                             xwd
libxt                            py-urwid                               xwininfo
libxtrap                         py-vcversioner                         xwud
libxtst                          py-virtualenv                          xz
libxv                            py-vsc-base                            yaml-cpp
libxvmc                          py-vsc-install                         yasm
libxxf86dga                      py-wcsaxes                             yorick
libxxf86misc                     py-wcwidth                             z3
libxxf86vm                       py-webkit-server                       zeromq
libyogrt                         py-werkzeug                            zfp
libzip                           py-wheel                               zip
likwid                           py-widgetsnbextension                  zlib
linux-headers                    py-wrapt                               zoltan
listres                          py-xarray                              zsh
llvm                             py-xlrd                                zstd

The packages are listed by name in alphabetical order. A pattern to match with no wildcards, * or ?, will be treated as though it started and ended with *, so util is equivalent to *util*. All patterns will be treated as case-insensitive. You can also add the -d to search the description of the package in addition to the name. Some examples:

All packages whose names contain “sql”:

$ spack list sql
postgresql  py-mysqldb1  py-sqlalchemy  r-rmysql  r-rpostgresql  r-rsqlite  sqlite

All packages whose names or descriptions contain documentation:

$ spack list --search-description documentation
compositeproto     libxfixes     py-docutils                  r-ggplot2   r-stanheaders
damageproto        libxpresent   py-epydoc                    r-quadprog  sowing
double-conversion  man-db        py-markdown                  r-rcpp      texinfo
doxygen            perl-dbfile   py-sphinx                    r-rinside   xorg-docs
gflags             py-alabaster  py-sphinxcontrib-websupport  r-roxygen2  xorg-sgml-doctools

spack info

To get more information on a particular package from spack list, use spack info. Just supply the name of a package:

$ spack info mpich
AutotoolsPackage:   mpich

Description:
    MPICH is a high performance and widely portable implementation of the
    Message Passing Interface (MPI) standard.

Homepage: http://www.mpich.org

Tags: 
    None

Preferred version:  
    3.2      http://www.mpich.org/static/downloads/3.2/mpich-3.2.tar.gz

Safe versions:  
    3.2      http://www.mpich.org/static/downloads/3.2/mpich-3.2.tar.gz
    3.1.4    http://www.mpich.org/static/downloads/3.1.4/mpich-3.1.4.tar.gz
    3.1.3    http://www.mpich.org/static/downloads/3.1.3/mpich-3.1.3.tar.gz
    3.1.2    http://www.mpich.org/static/downloads/3.1.2/mpich-3.1.2.tar.gz
    3.1.1    http://www.mpich.org/static/downloads/3.1.1/mpich-3.1.1.tar.gz
    3.1      http://www.mpich.org/static/downloads/3.1/mpich-3.1.tar.gz
    3.0.4    http://www.mpich.org/static/downloads/3.0.4/mpich-3.0.4.tar.gz

Variants:
    Name [Default]    Allowed values    Description


    hydra [on]        True, False       Build the hydra process
                                        manager
    pmi [on]          True, False       Build with PMI support
    romio [on]        True, False       Enable ROMIO MPI I/O
                                        implementation
    verbs [off]       True, False       Build support for OpenFabrics
                                        verbs.

Installation Phases:
    autoreconf    configure    build    install

Build Dependencies:
    None

Link Dependencies:
    None

Run Dependencies:
    None

Virtual Packages: 
    mpich@3: provides mpi@:3.0
    mpich@1: provides mpi@:1.3
    mpich provides mpi

Most of the information is self-explanatory. The safe versions are versions that Spack knows the checksum for, and it will use the checksum to verify that these versions download without errors or viruses.

Dependencies and virtual dependencies are described in more detail later.

spack versions

To see more available versions of a package, run spack versions. For example:

$ spack versions libelf
==> Safe versions (already checksummed):
  0.8.13  0.8.12
==> Remote versions (not yet checksummed):
  0.8.11  0.8.10  0.8.9  0.8.8  0.8.7  0.8.6  0.8.5  0.8.4  0.8.3  0.8.2  0.8.0  0.7.0  0.6.4  0.5.2

There are two sections in the output. Safe versions are versions for which Spack has a checksum on file. It can verify that these versions are downloaded correctly.

In many cases, Spack can also show you what versions are available out on the web—these are remote versions. Spack gets this information by scraping it directly from package web pages. Depending on the package and how its releases are organized, Spack may or may not be able to find remote versions.

Installing and uninstalling

spack install

spack install will install any package shown by spack list. For example, To install the latest version of the mpileaks package, you might type this:

$ spack install mpileaks

If mpileaks depends on other packages, Spack will install the dependencies first. It then fetches the mpileaks tarball, expands it, verifies that it was downloaded without errors, builds it, and installs it in its own directory under $SPACK_ROOT/opt. You’ll see a number of messages from spack, a lot of build output, and a message that the packages is installed:

$ spack install mpileaks
==> Installing mpileaks
==> mpich is already installed in ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/mpich@3.0.4.
==> callpath is already installed in ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/callpath@1.0.2-5dce4318.
==> adept-utils is already installed in ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/adept-utils@1.0-5adef8da.
==> Trying to fetch from https://github.com/hpc/mpileaks/releases/download/v1.0/mpileaks-1.0.tar.gz
######################################################################## 100.0%
==> Staging archive: ~/spack/var/spack/stage/mpileaks@1.0%gcc@4.4.7 arch=linux-debian7-x86_64-59f6ad23/mpileaks-1.0.tar.gz
==> Created stage in ~/spack/var/spack/stage/mpileaks@1.0%gcc@4.4.7 arch=linux-debian7-x86_64-59f6ad23.
==> No patches needed for mpileaks.
==> Building mpileaks.

... build output ...

==> Successfully installed mpileaks.
  Fetch: 2.16s.  Build: 9.82s.  Total: 11.98s.
[+] ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/mpileaks@1.0-59f6ad23

The last line, with the [+], indicates where the package is installed.

Building a specific version

Spack can also build specific versions of a package. To do this, just add @ after the package name, followed by a version:

$ spack install mpich@3.0.4

Any number of versions of the same package can be installed at once without interfering with each other. This is good for multi-user sites, as installing a version that one user needs will not disrupt existing installations for other users.

In addition to different versions, Spack can customize the compiler, compile-time options (variants), compiler flags, and platform (for cross compiles) of an installation. Spack is unique in that it can also configure the dependencies a package is built with. For example, two configurations of the same version of a package, one built with boost 1.39.0, and the other version built with version 1.43.0, can coexist.

This can all be done on the command line using the spec syntax. Spack calls the descriptor used to refer to a particular package configuration a spec. In the commands above, mpileaks and mpileaks@3.0.4 are both valid specs. We’ll talk more about how you can use them to customize an installation in Specs & dependencies.

spack uninstall

To uninstall a package, type spack uninstall <package>. This will ask the user for confirmation before completely removing the directory in which the package was installed.

$ spack uninstall mpich

If there are still installed packages that depend on the package to be uninstalled, spack will refuse to uninstall it.

To uninstall a package and every package that depends on it, you may give the --dependents option.

$ spack uninstall --dependents mpich

will display a list of all the packages that depend on mpich and, upon confirmation, will uninstall them in the right order.

A command like

$ spack uninstall mpich

may be ambiguous if multiple mpich configurations are installed. For example, if both mpich@3.0.2 and mpich@3.1 are installed, mpich could refer to either one. Because it cannot determine which one to uninstall, Spack will ask you either to provide a version number to remove the ambiguity or use the --all option to uninstall all of the matching packages.

You may force uninstall a package with the --force option

$ spack uninstall --force mpich

but you risk breaking other installed packages. In general, it is safer to remove dependent packages before removing their dependencies or use the --dependents option.

Non-Downloadable Tarballs

The tarballs for some packages cannot be automatically downloaded by Spack. This could be for a number of reasons:

  1. The author requires users to manually accept a license agreement before downloading (jdk and galahad).
  2. The software is proprietary and cannot be downloaded on the open Internet.

To install these packages, one must create a mirror and manually add the tarballs in question to it (see Mirrors):

  1. Create a directory for the mirror. You can create this directory anywhere you like, it does not have to be inside ~/.spack:

    $ mkdir ~/.spack/manual_mirror
    
  2. Register the mirror with Spack by creating ~/.spack/mirrors.yaml:

    mirrors:
      manual: file://~/.spack/manual_mirror
    
  3. Put your tarballs in it. Tarballs should be named <package>/<package>-<version>.tar.gz. For example:

    $ ls -l manual_mirror/galahad
    
    -rw-------. 1 me me 11657206 Jun 21 19:25 galahad-2.60003.tar.gz
    
  4. Install as usual:

    $ spack install galahad
    

Seeing installed packages

We know that spack list shows you the names of available packages, but how do you figure out which are already installed?

spack find

spack find shows the specs of installed packages. A spec is like a name, but it has a version, compiler, architecture, and build options associated with it. In spack, you can have many installations of the same package with different specs.

Running spack find with no arguments lists installed packages:

$ spack find
==> 74 installed packages.
-- linux-debian7-x86_64 / gcc@4.4.7 --------------------------------
ImageMagick@6.8.9-10  libdwarf@20130729  py-dateutil@2.4.0
adept-utils@1.0       libdwarf@20130729  py-ipython@2.3.1
atk@2.14.0            libelf@0.8.12      py-matplotlib@1.4.2
boost@1.55.0          libelf@0.8.13      py-nose@1.3.4
bzip2@1.0.6           libffi@3.1         py-numpy@1.9.1
cairo@1.14.0          libmng@2.0.2       py-pygments@2.0.1
callpath@1.0.2        libpng@1.6.16      py-pyparsing@2.0.3
cmake@3.0.2           libtiff@4.0.3      py-pyside@1.2.2
dbus@1.8.6            libtool@2.4.2      py-pytz@2014.10
dbus@1.9.0            libxcb@1.11        py-setuptools@11.3.1
dyninst@8.1.2         libxml2@2.9.2      py-six@1.9.0
fontconfig@2.11.1     libxml2@2.9.2      python@2.7.8
freetype@2.5.3        llvm@3.0           qhull@1.0
gdk-pixbuf@2.31.2     memaxes@0.5        qt@4.8.6
glib@2.42.1           mesa@8.0.5         qt@5.4.0
graphlib@2.0.0        mpich@3.0.4        readline@6.3
gtkplus@2.24.25       mpileaks@1.0       sqlite@3.8.5
harfbuzz@0.9.37       mrnet@4.1.0        stat@2.1.0
hdf5@1.8.13           ncurses@5.9        tcl@8.6.3
icu@54.1              netcdf@4.3.3       tk@src
jpeg@9a               openssl@1.0.1h     vtk@6.1.0
launchmon@1.0.1       pango@1.36.8       xcb-proto@1.11
lcms@2.6              pixman@0.32.6      xz@5.2.0
libdrm@2.4.33         py-dateutil@2.4.0  zlib@1.2.8

-- linux-debian7-x86_64 / gcc@4.9.2 --------------------------------
libelf@0.8.10  mpich@3.0.4

Packages are divided into groups according to their architecture and compiler. Within each group, Spack tries to keep the view simple, and only shows the version of installed packages.

spack find can filter the package list based on the package name, spec, or a number of properties of their installation status. For example, missing dependencies of a spec can be shown with --missing, packages which were explicitly installed with spack install <package> can be singled out with --explicit and those which have been pulled in only as dependencies with --implicit.

In some cases, there may be different configurations of the same version of a package installed. For example, there are two installations of libdwarf@20130729 above. We can look at them in more detail using spack find --deps, and by asking only to show libdwarf packages:

$ spack find --deps libdwarf
==> 2 installed packages.
-- linux-debian7-x86_64 / gcc@4.4.7 --------------------------------
    libdwarf@20130729-d9b90962
        ^libelf@0.8.12
    libdwarf@20130729-b52fac98
        ^libelf@0.8.13

Now we see that the two instances of libdwarf depend on different versions of libelf: 0.8.12 and 0.8.13. This view can become complicated for packages with many dependencies. If you just want to know whether two packages’ dependencies differ, you can use spack find --long:

$ spack find --long libdwarf
==> 2 installed packages.
-- linux-debian7-x86_64 / gcc@4.4.7 --------------------------------
libdwarf@20130729-d9b90962  libdwarf@20130729-b52fac98

Now the libdwarf installs have hashes after their names. These are hashes over all of the dependencies of each package. If the hashes are the same, then the packages have the same dependency configuration.

If you want to know the path where each package is installed, you can use spack find --paths:

$ spack find --paths
==> 74 installed packages.
-- linux-debian7-x86_64 / gcc@4.4.7 --------------------------------
    ImageMagick@6.8.9-10  ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/ImageMagick@6.8.9-10-4df950dd
    adept-utils@1.0       ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/adept-utils@1.0-5adef8da
    atk@2.14.0            ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/atk@2.14.0-3d09ac09
    boost@1.55.0          ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/boost@1.55.0
    bzip2@1.0.6           ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/bzip2@1.0.6
    cairo@1.14.0          ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/cairo@1.14.0-fcc2ab44
    callpath@1.0.2        ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/callpath@1.0.2-5dce4318
...

And, finally, you can restrict your search to a particular package by supplying its name:

$ spack find --paths libelf
-- linux-debian7-x86_64 / gcc@4.4.7 --------------------------------
    libelf@0.8.11  ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/libelf@0.8.11
    libelf@0.8.12  ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/libelf@0.8.12
    libelf@0.8.13  ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/libelf@0.8.13

spack find actually does a lot more than this. You can use specs to query for specific configurations and builds of each package. If you want to find only libelf versions greater than version 0.8.12, you could say:

$ spack find libelf@0.8.12:
-- linux-debian7-x86_64 / gcc@4.4.7 --------------------------------
    libelf@0.8.12  libelf@0.8.13

Finding just the versions of libdwarf built with a particular version of libelf would look like this:

$ spack find --long libdwarf ^libelf@0.8.12
==> 1 installed packages.
-- linux-debian7-x86_64 / gcc@4.4.7 --------------------------------
libdwarf@20130729-d9b90962

We can also search for packages that have a certain attribute. For example, spack find libdwarf +debug will show only installations of libdwarf with the ‘debug’ compile-time option enabled.

The full spec syntax is discussed in detail in Specs & dependencies.

Specs & dependencies

We know that spack install, spack uninstall, and other commands take a package name with an optional version specifier. In Spack, that descriptor is called a spec. Spack uses specs to refer to a particular build configuration (or configurations) of a package. Specs are more than a package name and a version; you can use them to specify the compiler, compiler version, architecture, compile options, and dependency options for a build. In this section, we’ll go over the full syntax of specs.

Here is an example of a much longer spec than we’ve seen thus far:

mpileaks @1.2:1.4 %gcc@4.7.5 +debug -qt arch=bgq_os ^callpath @1.1 %gcc@4.7.2

If provided to spack install, this will install the mpileaks library at some version between 1.2 and 1.4 (inclusive), built using gcc at version 4.7.5 for the Blue Gene/Q architecture, with debug options enabled, and without Qt support. Additionally, it says to link it with the callpath library (which it depends on), and to build callpath with gcc 4.7.2. Most specs will not be as complicated as this one, but this is a good example of what is possible with specs.

More formally, a spec consists of the following pieces:

  • Package name identifier (mpileaks above)
  • @ Optional version specifier (@1.2:1.4)
  • % Optional compiler specifier, with an optional compiler version (gcc or gcc@4.7.3)
  • + or - or ~ Optional variant specifiers (+debug, -qt, or ~qt) for boolean variants
  • name=<value> Optional variant specifiers that are not restricted to boolean variants
  • name=<value> Optional compiler flag specifiers. Valid flag names are cflags, cxxflags, fflags, cppflags, ldflags, and ldlibs.
  • target=<value> os=<value> Optional architecture specifier (target=haswell os=CNL10)
  • ^ Dependency specs (^callpath@1.1)

There are two things to notice here. The first is that specs are recursively defined. That is, each dependency after ^ is a spec itself. The second is that everything is optional except for the initial package name identifier. Users can be as vague or as specific as they want about the details of building packages, and this makes spack good for beginners and experts alike.

To really understand what’s going on above, we need to think about how software is structured. An executable or a library (these are generally the artifacts produced by building software) depends on other libraries in order to run. We can represent the relationship between a package and its dependencies as a graph. Here is the full dependency graph for mpileaks:

digraph { mpileaks -> mpich mpileaks -> callpath -> mpich callpath -> dyninst dyninst -> libdwarf -> libelf dyninst -> libelf }

Each box above is a package and each arrow represents a dependency on some other package. For example, we say that the package mpileaks depends on callpath and mpich. mpileaks also depends indirectly on dyninst, libdwarf, and libelf, in that these libraries are dependencies of callpath. To install mpileaks, Spack has to build all of these packages. Dependency graphs in Spack have to be acyclic, and the depends on relationship is directional, so this is a directed, acyclic graph or DAG.

The package name identifier in the spec is the root of some dependency DAG, and the DAG itself is implicit. Spack knows the precise dependencies among packages, but users do not need to know the full DAG structure. Each ^ in the full spec refers to some dependency of the root package. Spack will raise an error if you supply a name after ^ that the root does not actually depend on (e.g. mpileaks ^emacs@23.3).

Spack further simplifies things by only allowing one configuration of each package within any single build. Above, both mpileaks and callpath depend on mpich, but mpich appears only once in the DAG. You cannot build an mpileaks version that depends on one version of mpich and on a callpath version that depends on some other version of mpich. In general, such a configuration would likely behave unexpectedly at runtime, and Spack enforces this to ensure a consistent runtime environment.

The point of specs is to abstract this full DAG from Spack users. If a user does not care about the DAG at all, she can refer to mpileaks by simply writing mpileaks. If she knows that mpileaks indirectly uses dyninst and she wants a particular version of dyninst, then she can refer to mpileaks ^dyninst@8.1. Spack will fill in the rest when it parses the spec; the user only needs to know package names and minimal details about their relationship.

When spack prints out specs, it sorts package names alphabetically to normalize the way they are displayed, but users do not need to worry about this when they write specs. The only restriction on the order of dependencies within a spec is that they appear after the root package. For example, these two specs represent exactly the same configuration:

mpileaks ^callpath@1.0 ^libelf@0.8.3
mpileaks ^libelf@0.8.3 ^callpath@1.0

You can put all the same modifiers on dependency specs that you would put on the root spec. That is, you can specify their versions, compilers, variants, and architectures just like any other spec. Specifiers are associated with the nearest package name to their left. For example, above, @1.1 and %gcc@4.7.2 associates with the callpath package, while @1.2:1.4, %gcc@4.7.5, +debug, -qt, and target=haswell os=CNL10 all associate with the mpileaks package.

In the diagram above, mpileaks depends on mpich with an unspecified version, but packages can depend on other packages with constraints by adding more specifiers. For example, mpileaks could depend on mpich@1.2: if it can only build with version 1.2 or higher of mpich.

Below are more details about the specifiers that you can add to specs.

Version specifier

A version specifier comes somewhere after a package name and starts with @. It can be a single version, e.g. @1.0, @3, or @1.2a7. Or, it can be a range of versions, such as @1.0:1.5 (all versions between 1.0 and 1.5, inclusive). Version ranges can be open, e.g. :3 means any version up to and including 3. This would include 3.4 and 3.4.2. 4.2: means any version above and including 4.2. Finally, a version specifier can be a set of arbitrary versions, such as @1.0,1.5,1.7 (1.0, 1.5, or 1.7). When you supply such a specifier to spack install, it constrains the set of versions that Spack will install.

If the version spec is not provided, then Spack will choose one according to policies set for the particular spack installation. If the spec is ambiguous, i.e. it could match multiple versions, Spack will choose a version within the spec’s constraints according to policies set for the particular Spack installation.

Details about how versions are compared and how Spack determines if one version is less than another are discussed in the developer guide.

Compiler specifier

A compiler specifier comes somewhere after a package name and starts with %. It tells Spack what compiler(s) a particular package should be built with. After the % should come the name of some registered Spack compiler. This might include gcc, or intel, but the specific compilers available depend on the site. You can run spack compilers to get a list; more on this below.

The compiler spec can be followed by an optional compiler version. A compiler version specifier looks exactly like a package version specifier. Version specifiers will associate with the nearest package name or compiler specifier to their left in the spec.

If the compiler spec is omitted, Spack will choose a default compiler based on site policies.

Variants

Variants are named options associated with a particular package. They are optional, as each package must provide default values for each variant it makes available. Variants can be specified using a flexible parameter syntax name=<value>. For example, spack install libelf debug=True will install libelf build with debug flags. The names of particular variants available for a package depend on what was provided by the package author. spack info <package> will provide information on what build variants are available.

For compatibility with earlier versions, variants which happen to be boolean in nature can be specified by a syntax that represents turning options on and off. For example, in the previous spec we could have supplied libelf +debug with the same effect of enabling the debug compile time option for the libelf package.

Depending on the package a variant may have any default value. For libelf here, debug is False by default, and we turned it on with debug=True or +debug. If a variant is True by default you can turn it off by either adding -name or ~name to the spec.

There are two syntaxes here because, depending on context, ~ and - may mean different things. In most shells, the following will result in the shell performing home directory substitution:

mpileaks ~debug   # shell may try to substitute this!
mpileaks~debug    # use this instead

If there is a user called debug, the ~ will be incorrectly expanded. In this situation, you would want to write libelf -debug. However, - can be ambiguous when included after a package name without spaces:

mpileaks-debug     # wrong!
mpileaks -debug    # right

Spack allows the - character to be part of package names, so the above will be interpreted as a request for the mpileaks-debug package, not a request for mpileaks built without debug options. In this scenario, you should write mpileaks~debug to avoid ambiguity.

When spack normalizes specs, it prints them out with no spaces boolean variants using the backwards compatibility syntax and uses only ~ for disabled boolean variants. The - and spaces on the command line are provided for convenience and legibility.

Compiler Flags

Compiler flags are specified using the same syntax as non-boolean variants, but fulfill a different purpose. While the function of a variant is set by the package, compiler flags are used by the compiler wrappers to inject flags into the compile line of the build. Additionally, compiler flags are inherited by dependencies. spack install libdwarf cppflags="-g" will install both libdwarf and libelf with the -g flag injected into their compile line.

Notice that the value of the compiler flags must be quoted if it contains any spaces. Any of cppflags=-O3, cppflags="-O3", cppflags='-O3', and cppflags="-O3 -fPIC" are acceptable, but cppflags=-O3 -fPIC is not. Additionally, if they value of the compiler flags is not the last thing on the line, it must be followed by a space. The commmand spack install libelf cppflags="-O3"%intel will be interpreted as an attempt to set cppflags=”-O3%intel”`.

The six compiler flags are injected in the order of implicit make commands in GNU Autotools. If all flags are set, the order is $cppflags $cflags|$cxxflags $ldflags <command> $ldlibs for C and C++ and $fflags $cppflags $ldflags <command> $ldlibs for Fortran.

Compiler environment variables and additional RPATHs

In the exceptional case a compiler requires setting special environment variables, like an explicit library load path. These can bet set in an extra section in the compiler configuration. The user can also specify additional RPATHs that the compiler will add to all executables generated by that compiler. This is useful for forcing certain compilers to RPATH their own runtime libraries, so that executables will run without the need to set LD_LIBRARY_PATH.

compilers:
  - compiler:
      spec: gcc@4.9.3
      paths:
        cc: /opt/gcc/bin/gcc
        c++: /opt/gcc/bin/g++
        f77: /opt/gcc/bin/gfortran
        fc: /opt/gcc/bin/gfortran
      environment:
        set:
          LD_LIBRARY_PATH : /opt/gcc/lib
      extra_rpaths:
      - /path/to/some/compiler/runtime/directory
      - /path/to/some/other/compiler/runtime/directory

Architecture specifiers

The architecture can be specified by using the reserved words target and/or os (target=x86-64 os=debian7). You can also use the triplet form of platform, operating system and processor.

$ spack install libelf arch=cray-CNL10-haswell

Users on non-Cray systems won’t have to worry about specifying the architecture. Spack will autodetect what kind of operating system is on your machine as well as the processor. For more information on how the architecture can be used on Cray machines, see Spack on Cray

Virtual dependencies

The dependence graph for mpileaks we saw above wasn’t quite accurate. mpileaks uses MPI, which is an interface that has many different implementations. Above, we showed mpileaks and callpath depending on mpich, which is one particular implementation of MPI. However, we could build either with another implementation, such as openmpi or mvapich.

Spack represents interfaces like this using virtual dependencies. The real dependency DAG for mpileaks looks like this:

digraph { mpi [color=red] mpileaks -> mpi mpileaks -> callpath -> mpi callpath -> dyninst dyninst -> libdwarf -> libelf dyninst -> libelf }

Notice that mpich has now been replaced with mpi. There is no real MPI package, but some packages provide the MPI interface, and these packages can be substituted in for mpi when mpileaks is built.

You can see what virtual packages a particular package provides by getting info on it:

$ spack info mpich
AutotoolsPackage:   mpich

Description:
    MPICH is a high performance and widely portable implementation of the
    Message Passing Interface (MPI) standard.

Homepage: http://www.mpich.org

Tags: 
    None

Preferred version:  
    3.2      http://www.mpich.org/static/downloads/3.2/mpich-3.2.tar.gz

Safe versions:  
    3.2      http://www.mpich.org/static/downloads/3.2/mpich-3.2.tar.gz
    3.1.4    http://www.mpich.org/static/downloads/3.1.4/mpich-3.1.4.tar.gz
    3.1.3    http://www.mpich.org/static/downloads/3.1.3/mpich-3.1.3.tar.gz
    3.1.2    http://www.mpich.org/static/downloads/3.1.2/mpich-3.1.2.tar.gz
    3.1.1    http://www.mpich.org/static/downloads/3.1.1/mpich-3.1.1.tar.gz
    3.1      http://www.mpich.org/static/downloads/3.1/mpich-3.1.tar.gz
    3.0.4    http://www.mpich.org/static/downloads/3.0.4/mpich-3.0.4.tar.gz

Variants:
    Name [Default]    Allowed values    Description


    hydra [on]        True, False       Build the hydra process
                                        manager
    pmi [on]          True, False       Build with PMI support
    romio [on]        True, False       Enable ROMIO MPI I/O
                                        implementation
    verbs [off]       True, False       Build support for OpenFabrics
                                        verbs.

Installation Phases:
    autoreconf    configure    build    install

Build Dependencies:
    None

Link Dependencies:
    None

Run Dependencies:
    None

Virtual Packages: 
    mpich@3: provides mpi@:3.0
    mpich@1: provides mpi@:1.3
    mpich provides mpi

Spack is unique in that its virtual packages can be versioned, just like regular packages. A particular version of a package may provide a particular version of a virtual package, and we can see above that mpich versions 1 and above provide all mpi interface versions up to 1, and mpich versions 3 and above provide mpi versions up to 3. A package can depend on a particular version of a virtual package, e.g. if an application needs MPI-2 functions, it can depend on mpi@2: to indicate that it needs some implementation that provides MPI-2 functions.

Constraining virtual packages

When installing a package that depends on a virtual package, you can opt to specify the particular provider you want to use, or you can let Spack pick. For example, if you just type this:

$ spack install mpileaks

Then spack will pick a provider for you according to site policies. If you really want a particular version, say mpich, then you could run this instead:

$ spack install mpileaks ^mpich

This forces spack to use some version of mpich for its implementation. As always, you can be even more specific and require a particular mpich version:

$ spack install mpileaks ^mpich@3

The mpileaks package in particular only needs MPI-1 commands, so any MPI implementation will do. If another package depends on mpi@2 and you try to give it an insufficient MPI implementation (e.g., one that provides only mpi@:1), then Spack will raise an error. Likewise, if you try to plug in some package that doesn’t provide MPI, Spack will raise an error.

Specifying Specs by Hash

Complicated specs can become cumbersome to enter on the command line, especially when many of the qualifications are necessary to distinguish between similar installs. To avoid this, when referencing an existing spec, Spack allows you to reference specs by their hash. We previously discussed the spec hash that Spack computes. In place of a spec in any command, substitute /<hash> where <hash> is any amount from the beginning of a spec hash.

For example, lets say that you accidentally installed two different mvapich2 installations. If you want to uninstall one of them but don’t know what the difference is, you can run:

$ spack find --long mvapich2
==> 2 installed packages.
-- linux-centos7-x86_64 / gcc@6.3.0 ----------
qmt35td mvapich2@2.2%gcc
er3die3 mvapich2@2.2%gcc

You can then uninstall the latter installation using:

$ spack uninstall /er3die3

Or, if you want to build with a specific installation as a dependency, you can use:

$ spack install trilinos ^/er3die3

If the given spec hash is sufficiently long as to be unique, Spack will replace the reference with the spec to which it refers. Otherwise, it will prompt for a more qualified hash.

Note that this will not work to reinstall a dependency uninstalled by spack uninstall --force.

spack providers

You can see what packages provide a particular virtual package using spack providers. If you wanted to see what packages provide mpi, you would just run:

$ spack providers mpi
    intel-mpi                  mpich     mpich@3:  mvapich2@1.9   openmpi        openmpi@1.7.5:  spectrum-mpi
    intel-parallel-studio+mpi  mpich@1:  mvapich2  mvapich2@2.0:  openmpi@1.6.5  openmpi@2.0.0:

And if you only wanted to see packages that provide MPI-2, you would add a version specifier to the spec:

$ spack providers mpi@2
    intel-mpi                  mpich     mvapich2      mvapich2@2.0:  openmpi@1.6.5   openmpi@2.0.0:
    intel-parallel-studio+mpi  mpich@3:  mvapich2@1.9  openmpi        openmpi@1.7.5:  spectrum-mpi

Notice that the package versions that provide insufficient MPI versions are now filtered out.

Extensions & Python support

Spack’s installation model assumes that each package will live in its own install prefix. However, certain packages are typically installed within the directory hierarchy of other packages. For example, modules in interpreted languages like Python are typically installed in the $prefix/lib/python-2.7/site-packages directory.

Spack has support for this type of installation as well. In Spack, a package that can live inside the prefix of another package is called an extension. Suppose you have Python installed like so:

$ spack find python
==> 1 installed packages.
-- linux-debian7-x86_64 / gcc@4.4.7 --------------------------------
python@2.7.8

spack extensions

You can find extensions for your Python installation like this:

$ spack extensions python
==> python@2.7.8%gcc@4.4.7 arch=linux-debian7-x86_64-703c7a96
==> 36 extensions:
geos          py-ipython     py-pexpect    py-pyside            py-sip
py-basemap    py-libxml2     py-pil        py-pytz              py-six
py-biopython  py-mako        py-pmw        py-rpy2              py-sympy
py-cython     py-matplotlib  py-pychecker  py-scientificpython  py-virtualenv
py-dateutil   py-mpi4py      py-pygments   py-scikit-learn
py-epydoc     py-mx          py-pylint     py-scipy
py-gnuplot    py-nose        py-pyparsing  py-setuptools
py-h5py       py-numpy       py-pyqt       py-shiboken

==> 12 installed:
-- linux-debian7-x86_64 / gcc@4.4.7 --------------------------------
py-dateutil@2.4.0    py-nose@1.3.4       py-pyside@1.2.2
py-dateutil@2.4.0    py-numpy@1.9.1      py-pytz@2014.10
py-ipython@2.3.1     py-pygments@2.0.1   py-setuptools@11.3.1
py-matplotlib@1.4.2  py-pyparsing@2.0.3  py-six@1.9.0

==> None activated.

The extensions are a subset of what’s returned by spack list, and they are packages like any other. They are installed into their own prefixes, and you can see this with spack find --paths:

$ spack find --paths py-numpy
==> 1 installed packages.
-- linux-debian7-x86_64 / gcc@4.4.7 --------------------------------
    py-numpy@1.9.1  ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/py-numpy@1.9.1-66733244

However, even though this package is installed, you cannot use it directly when you run python:

$ spack load python
$ python
Python 2.7.8 (default, Feb 17 2015, 01:35:25)
[GCC 4.4.7 20120313 (Red Hat 4.4.7-11)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import numpy
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: No module named numpy
>>>

Extensions & Environment Modules

There are two ways to get numpy working in Python. The first is to use Using module files via Spack. You can simply use or load the module for the extension, and it will be added to the PYTHONPATH in your current shell.

For tcl modules:

$ spack load python
$ spack load py-numpy

or, for dotkit:

$ spack use python
$ spack use py-numpy

Now import numpy will succeed for as long as you keep your current session open.

Activating Extensions

It is often desirable to have certain packages always available as part of a Python installation. Spack offers a more permanent solution for this case. Instead of requiring users to load particular environment modules, you can activate the package within the Python installation:

spack activate

$ spack activate py-numpy
==> Activated extension py-setuptools@11.3.1%gcc@4.4.7 arch=linux-debian7-x86_64-3c74eb69 for python@2.7.8%gcc@4.4.7.
==> Activated extension py-nose@1.3.4%gcc@4.4.7 arch=linux-debian7-x86_64-5f70f816 for python@2.7.8%gcc@4.4.7.
==> Activated extension py-numpy@1.9.1%gcc@4.4.7 arch=linux-debian7-x86_64-66733244 for python@2.7.8%gcc@4.4.7.

Several things have happened here. The user requested that py-numpy be activated in the python installation it was built with. Spack knows that py-numpy depends on py-nose and py-setuptools, so it activated those packages first. Finally, once all dependencies were activated in the python installation, py-numpy was activated as well.

If we run spack extensions again, we now see the three new packages listed as activated:

$ spack extensions python
==> python@2.7.8%gcc@4.4.7  arch=linux-debian7-x86_64-703c7a96
==> 36 extensions:
geos          py-ipython     py-pexpect    py-pyside            py-sip
py-basemap    py-libxml2     py-pil        py-pytz              py-six
py-biopython  py-mako        py-pmw        py-rpy2              py-sympy
py-cython     py-matplotlib  py-pychecker  py-scientificpython  py-virtualenv
py-dateutil   py-mpi4py      py-pygments   py-scikit-learn
py-epydoc     py-mx          py-pylint     py-scipy
py-gnuplot    py-nose        py-pyparsing  py-setuptools
py-h5py       py-numpy       py-pyqt       py-shiboken

==> 12 installed:
-- linux-debian7-x86_64 / gcc@4.4.7 --------------------------------
py-dateutil@2.4.0    py-nose@1.3.4       py-pyside@1.2.2
py-dateutil@2.4.0    py-numpy@1.9.1      py-pytz@2014.10
py-ipython@2.3.1     py-pygments@2.0.1   py-setuptools@11.3.1
py-matplotlib@1.4.2  py-pyparsing@2.0.3  py-six@1.9.0

==> 3 currently activated:
-- linux-debian7-x86_64 / gcc@4.4.7 --------------------------------
py-nose@1.3.4  py-numpy@1.9.1  py-setuptools@11.3.1

Now, when a user runs python, numpy will be available for import without the user having to explicitly loaded. python@2.7.8 now acts like a system Python installation with numpy installed inside of it.

Spack accomplishes this by symbolically linking the entire prefix of the py-numpy into the prefix of the python package. To the python interpreter, it looks like numpy is installed in the site-packages directory.

The only limitation of activation is that you can only have a single version of an extension activated at a time. This is because multiple versions of the same extension would conflict if symbolically linked into the same prefix. Users who want a different version of a package can still get it by using environment modules, but they will have to explicitly load their preferred version.

spack activate --force

If, for some reason, you want to activate a package without its dependencies, you can use spack activate --force:

$ spack activate --force py-numpy
==> Activated extension py-numpy@1.9.1%gcc@4.4.7 arch=linux-debian7-x86_64-66733244 for python@2.7.8%gcc@4.4.7.

spack deactivate

We’ve seen how activating an extension can be used to set up a default version of a Python module. Obviously, you may want to change that at some point. spack deactivate is the command for this. There are several variants:

  • spack deactivate <extension> will deactivate a single extension. If another activated extension depends on this one, Spack will warn you and exit with an error.

  • spack deactivate --force <extension> deactivates an extension regardless of packages that depend on it.

  • spack deactivate --all <extension> deactivates an extension and all of its dependencies. Use --force to disregard dependents.

  • spack deactivate --all <extendee> deactivates all activated extensions of a package. For example, to deactivate all python extensions, use:

    $ spack deactivate --all python
    

Filesystem requirements

Spack currently needs to be run from a filesystem that supports flock locking semantics. Nearly all local filesystems and recent versions of NFS support this, but parallel filesystems may be mounted without flock support enabled. You can determine how your filesystems are mounted with mount -p. The output for a Lustre filesystem might look like this:

$ mount -l | grep lscratch
pilsner-mds1-lnet0@o2ib100:/lsd on /p/lscratchd type lustre (rw,nosuid,noauto,_netdev,lazystatfs,flock)
porter-mds1-lnet0@o2ib100:/lse on /p/lscratche type lustre (rw,nosuid,noauto,_netdev,lazystatfs,flock)

Note the flock option on both Lustre mounts. If you do not see this or a similar option for your filesystem, you may need ot ask your system administrator to enable flock.

This issue typically manifests with the error below:

$ ./spack find
Traceback (most recent call last):
File "./spack", line 176, in <module>
  main()
File "./spack", line 154,' in main
  return_val = command(parser, args)
File "./spack/lib/spack/spack/cmd/find.py", line 170, in find
  specs = set(spack.installed_db.query(\**q_args))
File "./spack/lib/spack/spack/database.py", line 551, in query
  with self.read_transaction():
File "./spack/lib/spack/spack/database.py", line 598, in __enter__
  if self._enter() and self._acquire_fn:
File "./spack/lib/spack/spack/database.py", line 608, in _enter
  return self._db.lock.acquire_read(self._timeout)
File "./spack/lib/spack/llnl/util/lock.py", line 103, in acquire_read
  self._lock(fcntl.LOCK_SH, timeout)   # can raise LockError.
File "./spack/lib/spack/llnl/util/lock.py", line 64, in _lock
  fcntl.lockf(self._fd, op | fcntl.LOCK_NB)
IOError: [Errno 38] Function not implemented

A nicer error message is TBD in future versions of Spack.

Getting Help

spack help

If you don’t find what you need here, the help subcommand will print out out a list of all of spack’s options and subcommands:

$ spack help
usage: spack [-hkVcolor] <command> [...]

A flexible package manager that supports multiple versions,
configurations, platforms, and compilers.

These are common spack commands:

query packages:
  list                  list and search available packages
  info                  get detailed information on a particular package
  find                  list and search installed packages

build packages:
  install               build and install packages
  uninstall             remove installed packages
  spec                  show what would be installed, given a spec

environment:
  load                  add package to environment using `module load`
  module                manipulate module files
  unload                remove package from environment using `module unload`
  view                  produce a single-rooted directory view of packages

create packages:
  create                create a new package file
  edit                  open package files in $EDITOR

system:
  arch                  print architecture information about this machine
  compilers             list available compilers

optional arguments:
  -h, --help            show this help message and exit
  -k, --insecure        do not check ssl certificates when downloading
  -V, --version         show version number and exit
  --color {always,never,auto}
                        when to colorize output; default is auto

more help:
  spack help -a          list all available commands
  spack help <command>   help on a specific command
  spack help --spec      help on the spec syntax
  spack docs             open http://spack.rtfd.io/ in a browser

Adding an argument, e.g. spack help <subcommand>, will print out usage information for a particular subcommand:

$ spack help install
usage: spack install [-h] [--only {package,dependencies}] [-j JOBS]
                     [--keep-prefix] [--keep-stage] [--restage]
                     [--show-log-on-error] [--source] [-n] [-v] [--fake] [-f]
                     [--clean | --dirty] [--run-tests] [--log-format {junit}]
                     [--log-file LOG_FILE]
                     ...

build and install packages

positional arguments:
  package               spec of the package to install

optional arguments:
  -h, --help            show this help message and exit
  --only {package,dependencies}
                        select the mode of installation. the default is to
                        install the package along with all its dependencies.
                        alternatively one can decide to install only the
                        package or only the dependencies
  -j JOBS, --jobs JOBS  explicitly set number of make jobs. default is #cpus
  --keep-prefix         don't remove the install prefix if installation fails
  --keep-stage          don't remove the build stage if installation succeeds
  --restage             if a partial install is detected, delete prior state
  --show-log-on-error   print full build log to stderr if build fails
  --source              install source files in prefix
  -n, --no-checksum     do not check packages against checksum
  -v, --verbose         display verbose build output while installing
  --fake                fake install. just remove prefix and create a fake
                        file
  -f, --file            install from file. Read specs to install from .yaml
                        files
  --clean               sanitize the environment from variables that can
                        affect how packages find libraries or headers
  --dirty               maintain the current environment without trying to
                        sanitize it
  --run-tests           run package level tests during installation
  --log-format {junit}  format to be used for log files
  --log-file LOG_FILE   filename for the log file. if not passed a default
                        will be used

Alternately, you can use spack --help in place of spack help, or spack <subcommand> --help to get help on a particular subcommand.