[Buildbot-devel] Buildbot through stacktrace during SVNPoller

[Dustin J. Mitchell]

On Tue, Jun 14, 2011 at 6:54 PM, William Deegan
<bill at baddogconsulting.com> wrote:
> Fulvio,
>
> The machine is running buildbot + svn + a few nx hosts.
> The startup in question doesn't have a lot of hardware and will likely be migrating everything but svn off of that machine in the near term.
> It's centos 5.5 64 bit linux.
>
> Buildbot's eating ~1GB
> SVN+ Subversion edge (activestate) eating another 1GB
> So that doesn't leave a whole lot for the rest.
> 16GB should be sufficient.

At Mozilla, we've had some problems with Buildbot eating a lot of
memory.  It's still not clear what portion of that is due to internal
extensions to buildbot, rather than things that are in the Buildbot
repository itself.  Running Python code (and Buildbot pulls in a lot
of it - Twisted is not small) uses a lot of RAM, and on a 64-bit
system just about everything in Python takes twice as much space, so
1GB doesn't surprise me that much.

That said, we've seen the same problem with ENOMEM from fork().  It
turns out, fork() will not allow you to over-commit memory, so to
fork() you need space free (between swap and RAM) equivalent to the
virtual size of the forking process - which is a lot for the
buildmaster.

Dustin