|Version 2 (modified by guest, 6 years ago) (diff)|
OProfile does a system-wide profile using performance counters. It can also generate annotated source/assembly just like VTune. Unfortunately, because GHC can't export source-level debugging symbols, OProfile cannot do source-level annotation of GHC programs.
It can be installed from a package on Ubuntu, which is cool. But beware: Ubuntu bug 172495: https://bugs.launchpad.net/ubuntu/+source/oprofile/+bug/172495/ : change the /bin/sh to /bin/bash at the top of /usr/bin/opcontrol.
There seems to be a problem with the counters just stopping arbitrarily, requiring a restart of the daemon.
Recipe for profiling something:
$ sudo opcontrol --init $ sudo opcontrol --reset $ sudo opcontrol --setup --event=<event> $ sudo opcontrol --start $ ... run program... $ sudo opcontrol --stop $ sudo opreport
check that the program you ran is at the top of the profile somewhere. Sometimes for me it doesn't appear, and have to run it again. To see a list of possible <event>s, use
$ opcontrol --list-events
Then to annotate the source:
$ sudo opannotate --source <program> >&! log}}} lists the contents of source files in order of importance. Alternatively use --output-dir to put the source files in a directory, but then you don't get to find out which are the important ones.