[Buildbot-devel] Scaling buildbot

[Dan Kegel]

On Thu, Jun 11, 2015 at 3:50 PM, Jim Rowan <jmr at computing.com> wrote:
> Use your favorite sysadmin tools to figure out if it’s cpu, disk, or memory bound…  (Is this a small machine?  Does it have enough memory?  Is everything on local disk, or is NFS involved?   Is your disk “fast”?)

No NFS.  The box is a bunch of Xeons running vmware instances.  This
instance has 8 GB of RAM.  ps says:

$ ps augxw
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
buildbot  4239 30.5  5.8 1705764 475356 ?      Ssl  12:58 151:04
python twistd --pidfile
/home/buildbot/master-state/sandbox/g-speak/twistd.pid ...

That process' cpu usage bounces around a lot; in 8 hours, it racked up
about 2 hours of CPU time.
When there are git zombies, twistd uses 100% of CPU.

cat /proc/cpuinfo says there are four cores of type
Intel(R) Xeon(R) CPU           X5450  @ 3.00GHz
which probably isn't too far off from the truth.

I think disk is fast, but, um, I haven't measured it.