June282016 - openpmix/openpmix GitHub Wiki

##PMIx Developers Meeting

June 28, 2016

Ralph, Annu, Artem, Chris, Charles, David, Gary, Todd and Anandhi.

• 1.1.4 release is out and is being picked up by distros.
• MCA plugin framework implementation is progressing well. Testing of inter-versioning is ongoing, requires infrastructure to cache the data returned by the RM until the client connects and pack the data according to the comm plugin for the client's version.
• IBM is seeing a performance issue running 160 ranks on 160 cpus, on a single host, it took 18 secs to get to MPI_init. Root caused to a flood of get requests (N square) to the local server. PAMI is issuing the gets for all ranks. 1.1.2 no performance issue same test completes in 2 secs. This could be because of PMIx server is calling the local RM server for data, because all ranks are asking for all other rank data at about the same time, instead the PMIx server should look in the shared memory. This is a mode that would be implemented in the DSTOR. This could be an issue with PAMI forcing PMIx to do extra gets to the server as they may be doing a get on PAMI defined key.
• DSTOR PR is being tested with OMPI, Mellanox is seeing an issue with the API changes - PMIx_init is failing with too few arguments. This could be a config issue that is not picking up the right PMIx external component (1.1.4 vs 2.0)
• Provide an API to get PMIx version to resolve API changes, but this causes cross compiling issues especially with OMPI. We can use autoconf to get the version string without needing to compile PMIx using nm. There is a shell script in the config directory, to get PMIx version, that can be used without causing cross compile issues. The config files are not installed currently, but we can install them if needed. Artem proposed an alternative to use Macro in pmix.h, which is already included in the program, so the program can call those macros.
• Ralph to put the version string from auto conf and put it in pmix.h i.e. add appropriate Macros