Bug 1232504

Summary: [Proposal] Adapt find-requires and find-provides to encode MPI implementation in provides string
Product: [Fedora] Fedora Reporter: Sandro Mani <manisandro>
Component: rpmAssignee: Packaging Maintenance Team <packaging-team-maint>
Status: CLOSED WONTFIX QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: rawhideCC: jzeleny, lkardos, novyjindrich, packaging-team-maint, pbrobinson, pknirsch
Target Milestone: ---   
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2015-06-18 23:25:58 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description Sandro Mani 2015-06-16 22:40:26 UTC 
Description of problem:
Currently, the packages libfoo, libfoo-openmpi and libfoo-mpich providing the library libfoo.so all have a provides string of i.e.

libfoo.so()(64bit)

While yum used a shortest-package-name rule to choose which package to pick, dnf does not have any rules, and seems to just pick the first match it comes across. Currently the only solution would be to filter the provides from the -openmpi, -mpich packages and add explicit Requires: where needed. I'd like to propose to extend the provides string in such way that it also encodes the MPI implementation, i.e.:

$ rpm -qp --provides libfoo
libfoo.so()(64bit)

$ rpm -qp --provides libfoo-mpich
libfoo.so()(64bit)(mpich-x86_64)

$ rpm -qp --provides libfoo-openmpi
libfoo.so()(64bit)(openmpi-x86_64)

To this end, I'm proposing to adapt the find-requires and find-provides scripts as (or similarly to):
- https://smani.fedorapeople.org/find-provides
- https://smani.fedorapeople.org/find-requires

See also [1] for the discussion on fedora-devel leading to this change proposal.

[1] https://lists.fedoraproject.org/pipermail/devel/2015-June/211318.html

To coordinate the needed mass rebuild of MPI packages, I'm drafting a change at 
https://fedoraproject.org/wiki/User:Smani/RpmMPIReqProv
Comment 1 Sandro Mani 2015-06-16 22:49:01 UTC 
To clarify one thing: I initially thought of having these scripts included as mpi-find-requires and mpi-find-provides and have a %{?mpi_package_header} to override __find_requires and __find_provides, however I wonder whether it is not easier to just have it globally enabled, to remove the risk of inconsistencies between regular find-{requires,provides} and mpi-find-{requires,provides}. But I'm happy either way.
Comment 2 Sandro Mani 2015-06-18 23:25:58 UTC 
A nice explanation by T.C. Hollingsworth [1] explained how to implement this the right way, so I'm closing this bug and I'll proceed with the outlined strategy.

[1] https://lists.fedoraproject.org/pipermail/devel/2015-June/211570.html