CPU Profiling¶
If you built Ceph from source and compiled Ceph for use with oprofile you can profile Ceph’s CPU usage. See Installing Oprofile for details.
Initializing oprofile¶
The first time you use oprofile you need to initialize it. Locate the
vmlinux image corresponding to the kernel you are now running.
ls /boot
sudo opcontrol --init
sudo opcontrol --setup --vmlinux={path-to-image} --separate=library --callgraph=6
Starting oprofile¶
To start oprofile execute the following command:
opcontrol --start
Once you start oprofile, you may run some tests with Ceph.
Stopping oprofile¶
To stop oprofile execute the following command:
opcontrol --stop
Retrieving oprofile Results¶
To retrieve the top cmon results, execute the following command:
opreport -gal ./cmon | less
To retrieve the top cmon results with call graphs attached, execute the
following command:
opreport -cal ./cmon | less
Important
After reviewing results, you should reset oprofile before
running it again. Resetting oprofile removes data from the session
directory.
Resetting oprofile¶
To reset oprofile, execute the following command:
sudo opcontrol --reset
Important
You should reset oprofile after analyzing data so that
you do not commingle results from different tests.
