[tproxy] anything known about potential memory leaks in tproxy 1.1.3 ?

KOVACS Krisztian hidden@balabit.hu
Tue, 06 Apr 2004 11:50:09 +0200


On Fri, 2004-04-02 at 09:53, Lennert Buytenhek wrote:
> Our production firewall/transproxy suddenly became _really_ unresponsive
> a few days ago after ~120 days of uptime, from what seems to have been a
> memory leak.
> The machine has 1GB of memory, but the amount of page cache was really small,
> the number of processes waiting for disk I/O was about 30, and at avg 4MB/sec
> reading from disk it was seeking all over the place.  Also, bash would
> sometimes say something along the lines of 'resource unavailable' when
> starting subprocesses.
> Temporarily disabling the transproxy function by deleting the redirect rule
> caused the disk to go idle (our transproxy-using app intercepts HTTP requests
> and answers the requests locally for static data, fileset is about 5GB but
> ~200MB of it accounts for 90% of the hits.)  But every little thing that I
> tried, even an ls or a grep in /etc caused massive disk I/O.
> I hastily rebooted the machine and thus have no ways of debugging this
> anymore.  But I was wondering, is anything known about memory leaks in the
> 1.1.3 version of the tproxy code?  I checked the changelogs, but couldn't
> find anything related to memleaks.
> Should I schedule maintenance to move the machine to 1.9.1?  Any other
> advice?  (It's not a problem for me to schedule the machine to be rebooted
> every 90 days or something like that.)

  We've also found signs that suggest that there may be a possible
memory leak in tproxy (it seemed to leak conntrack entries). However, I
don't have an idea what the problem might be, so it's not fixed yet.

  Could you provide a bit more information? Is this system SMP or UP?
I'd be happy to receive the contents of /proc/slabinfo, if possible,
daily/hourly snapshots.

  Moving to 1.9.1 is not recommended in your case, its ABI/API is
incompatible (though trivial to fix in your sources), and probably won't

   Krisztian KOVACS