Oprofile is a kernel based profiler on Linux. It is an excellent tool for system wide profiling. If MPD is slow, or you suspect it consumes too much CPU, we would like to see your oprofile report.
You have to use an oprofile enabled kernel. Most distributions ship oprofile as a kernel module. Load it with "modprobe oprofile".
Install the oprofile userspace utilities: "apt-get install oprofile" on Debian. Be sure to have a MPD with debugging symbols (package "mpd-dbg" on Debian).
Start MPD, and start the oprofile (as root):
opcontrol --reset opcontrol --start
Now use MPD. Let it play something, trigger the problem where it consumes too much CPU. Let it run a few minutes. Then stop the oprofile:
To generate the report, type:
opreport -g --symbols
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