Valgrind can be used to bebug and profile applications.  A variety of tools are supported [ --tool=...].  Popular tools are memcheck (the default) to check for memory leaks, cachegrind reporting cache utilization, and callgrind profiling.

Here is the basic usage information along with an example showing memcheck:

# load the module

module load valgrind

 

# target istanbul for cache matchup [ cachegrind ]

cc -g -hcpu=istanbul stream.c

 

# run with valgrind ( --tool=cachegrind is also ok )

 

aprun -n 1 valgrind ./a.out

 

# output:

 

==28378== Memcheck, a memory error detector

==28378== Copyright (C) 2002-2013, and GNU GPL'd, by Julian Seward et al.

==28378== Using Valgrind-3.9.0 and LibVEX; rerun with -h for copyright info

==28378== Command: ./a.out

...

 

==28379==     in use at exit: 0 bytes in 0 blocks

==28379==   total heap usage: 0 allocs, 0 frees, 0 bytes allocated

==28379== 

==28379== All heap blocks were freed -- no leaks are possible

==28379== 

==28379== For counts of detected and suppressed errors, rerun with: -v

==28379== Use --track-origins=yes to see where uninitialised values come from

==28379== ERROR SUMMARY: 2183 errors from 89 contexts (suppressed: 0 from 0)

==28378== Use of uninitialised value of size 8

==28378==    at 0x201D51CB: __run_exit_handlers (exit.c:78)

==28378== 

==28378== 

==28378== HEAP SUMMARY:

==28378==     in use at exit: 0 bytes in 0 blocks

==28378==   total heap usage: 0 allocs, 0 frees, 0 bytes allocated

==28378== 

==28378== All heap blocks were freed -- no leaks are possible

==28378== 

==28378== For counts of detected and suppressed errors, rerun with: -v

==28378== Use --track-origins=yes to see where uninitialised values come from

==28378== ERROR SUMMARY: 185 errors from 7 contexts (suppressed: 0 from 0)

Application 5648105 resources: utime ~11s, stime ~0s, Rss ~106824, inblocks ~114

34, outblocks ~223