Spack should be more aggressive about reusing installed software #311
Description
When I have [email protected] installed:
(cab689):~$ spack find python
==> 1 installed packages.
-- chaos_5_x86_64_ib / [email protected] --------------------------------
[email protected]
I now try to install py-twisted, explicitly setting the dependency ^[email protected]:
(cab689):~$ spack install -v py-twisted^[email protected]
==> Installing py-twisted
==> Installing python
==> bzip2 is already installed in /g/g22/gimenez1/src/spack/opt/spack/chaos_5_x86_64_ib/gcc-4.9.2/bzip2-1.0.6-wl4v7wdok42cfndertdgyxys2au2ljpz.
==> ncurses is already installed in /g/g22/gimenez1/src/spack/opt/spack/chaos_5_x86_64_ib/gcc-4.9.2/ncurses-6.0-2v7r63atwq6aw3p66bc3mkp7hxeoxgqx.
==> zlib is already installed in /g/g22/gimenez1/src/spack/opt/spack/chaos_5_x86_64_ib/gcc-4.9.2/zlib-1.2.8-mbw4kksfiiloopjcuqbwrktbxe7hq73x.
==> openssl is already installed in /g/g22/gimenez1/src/spack/opt/spack/chaos_5_x86_64_ib/gcc-4.9.2/openssl-1.0.2e-qs3iwf2rhwlck3qsyrlea7i7zbxluntg.
==> sqlite is already installed in /g/g22/gimenez1/src/spack/opt/spack/chaos_5_x86_64_ib/gcc-4.9.2/sqlite-3.8.5-2fhvbyidf72xkkazmqnng4ofp2z2hgxk.
==> readline is already installed in /g/g22/gimenez1/src/spack/opt/spack/chaos_5_x86_64_ib/gcc-4.9.2/readline-6.3-zclrirpahthnvxm2kj2qbz3rup6agcg5.
==> Already downloaded /g/g22/gimenez1/src/spack/var/spack/stage/python-2.7.10-4azwfxr6b6fddsanso7fgk5xivgdnffs/Python-2.7.10.tar.xz.
As you can see, spack tries to reinstall python 2.7.10.
I went ahead with the installation to see the dependency graph of the new python, here it is:
(cab689):~$ spack find -d python
==> 2 installed packages.
-- chaos_5_x86_64_ib / [email protected] --------------------------------
[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
The newly installed python has ^zlib, everything else is the same. py-twisted does not, however, depend on python^zlib, so not sure why spack is making this new dependency requirement. To verify that py-twisted is using the new python^zlib:
(cab689):~$ spack find -d py-twisted
==> 1 installed packages.
-- chaos_5_x86_64_ib / [email protected] --------------------------------
[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
^[email protected]
TL;DR py-twisted should use the existing python, but it creates a new python^zlib for no apparent reason.