MemP

memP is a LLNL developed, light weight, parallel heap profiling library to identify the heap allocation that causes an MPI task to reach its memory in use high water mark (HWM).

memP Reports

Summary Report: Generated from within MPI_Finalize, this report describes the memory HWM of each task over the run of the application. This can be used to determine which task allocates the most memory and how this compares to the memory of other tasks.

Task Report: Based on specific criteria, a report can be generated for each task, that provides a snapshot of the heap memory currently in use, including the amount allocated at specific call sites.

Using memP

Load the memp Module

module load memP

Compile with the recommended BG/Q flags and link your application with the required libraries:

-Wl,-zmuldefs ${SCINET_LIB_MB}

Examples:

mpixlc -g -Wl,-zmuldefs -o myprog myprog.c -L/usr/local/tools/memP/lib -lmemP
mpixlf77 -g -Wl,-zmuldefs -o myprog myprog.f -L/usr/local/tools/memP/lib -lmemP 

Then run your MPI application as usual and you will see an memP header and traile it sends to stdout, as well as the output file generated at the end of the run.

Output Options

See [ http://memp.sourceforge.net/ ] for full details.