This all sounds good to me! On Apr 29, 2008, at 6:35 PM, Josh Hursey wrote:
What: Add mca_base_select() and adjust frameworks & components to use it. Why: Consolidation of code for general goodness. Where: https://svn.open-mpi.org/svn/ompi/tmp-public/jjh-mca-play When: Code ready now. Documentation ready soon. Timeout: May 6, 2008 (After teleconf) [1 week] Discussion: ----------- For a number of years a few developers have been talking about creating a MCA base component selection function. For various reasons this was never implemented. Recently I decided to give it a try. A base select function will allow Open MPI to provide completely consistent selection behavior for many of its frameworks (18 of 31 to be exact at the moment). The primary goal of this work is to improving code maintainability through code reuse. Other benefits also result such as a slightly smaller memory footprint. The mca_base_select() function represented the most commonly used logic for component selection: Select the one component with the highest priority and close all of the not selected components. This function can be found at the path below in the branch: opal/mca/base/mca_base_components_select.c To support this I had to formalize a query() function in the mca_base_component_t of the form: int mca_base_query_component_fn(mca_base_module_t **module, int *priority); This function is specified after the open and close component functions in this structure as to allow compatibility with frameworks that do not use the base selection logic. Frameworks that do *not* use this function are *not* effected by this commit. However, every component in the frameworks that use the mca_base_select function must adjust their component query function to fit that specified above. 18 frameworks in Open MPI have been changed. I have updated all of the components in the 18 frameworks available in the trunk on my branch. The effected frameworks are: - OPAL Carto - OPAL crs - OPAL maffinity - OPAL memchecker - OPAL paffinity - ORTE errmgr - ORTE ess - ORTE Filem - ORTE grpcomm - ORTE odls - ORTE pml - ORTE ras - ORTE rmaps - ORTE routed - ORTE snapc - OMPI crcp - OMPI dpm - OMPI pubsub There was a question of the memory footprint change as a result of this commit. I used 'pmap' to determine process memory footprint of a hello world MPI program. Static and Shared build numbers are below along with variations on launching locally and to a single node allocated by SLURM. All of this was on Indiana University's Odin machine. We compare against the trunk (r18276) representing the last SVN sync point of the branch. Process(shared)| Trunk | Branch | Diff (Improvement) ---------------+----------+---------+------- mpirun (orted) | 39976K | 36828K | 3148K hello (0) | 229288K | 229268K | 20K hello (1) | 229288K | 229268K | 20K ---------------+----------+---------+------- mpirun | 40032K | 37924K | 2108K orted | 34720K | 34660K | 60K hello (0) | 228404K | 228384K | 20K hello (1) | 228404K | 228384K | 20K Process(static)| Trunk | Branch | Diff (Improvement) ---------------+----------+---------+------- mpirun (orted) | 21384K | 21372K | 12K hello (0) | 194000K | 193980K | 20K hello (1) | 194000K | 193980K | 20K ---------------+----------+---------+------- mpirun | 21384K | 21372K | 12K orted | 21208K | 21196K | 12K hello (0) | 193116K | 193096K | 20K hello (1) | 193116K | 193096K | 20K As you can see there are some small memory footprint improvements on my branch that result from this work. The size of the Open MPI project shrinks a bit as well. This commit cuts between 3,500 and 2,000 lines of code (depending on how you count) so about a ~1% code shrink. The branch is stable in all of the testing I have done, but there are some platforms on which I cannot test. So please give this branch a try and let me know if you find any problems. Cheers, Josh _______________________________________________ devel mailing list de...@open-mpi.org http://www.open-mpi.org/mailman/listinfo.cgi/devel
-- Jeff Squyres Cisco Systems
