The Matlab profiler is a powerful tool for debugging performance-related issues in Matlab applications. However, it also has some undocumented options that facilitate other forms of debugging, namely memory bottlenecks and JIT (Just-In-Time compilation) problems.
To turn on memory stats in the profile report, run this (only once is necessary – will be remembered for future profiling runs):
profile -memory on; profile('-memory','on'); % an alternative
To turn on JIT information, run this (again, only once is necessary, prior to profile report):
setpref('profiler','showJitLines',1);
You will then see additional JIT and memory (allocated, freed and peak) information displayed in the profile report, as well as the options to sort by allocated, freed and peak memory:
Profile report with memory & JIT info
For those interested, the references to these two options appear within the code of profview.m (line 1199 on R2007b), for the JIT option:
showJitLines = getpref('profiler','showJitLines',false);
…and profile.m (lines 163-165 on R2007b), for the memory option:
if memory ~= -1 callstats('memory', memory); end
Note that there appears to be two undocumented additional memory-related options in profile.m (lines 311-312):
options = {'detail', 'timer', 'history', 'nohistory', 'historysize', ...
'timestamp', 'memory', 'callmemory', 'nomemory' };
However, ‘-nomemory’ appears to simply turn the memory stats collection off, and ‘-callmemory’ is not recognized because of a bug in line 349, which looks for ‘callnomemory’…:
case 'callnomemory' % should be 'callmemory' memory = 2;
When this bug is fixed, we see that we get only partial memory information, so the ‘-callmemory’ option is really not useful – use ‘-memory’ instead.
