[rsyslog] memory alloc problems - any advise?

[Rainer Gerhards]

> -----Original Message-----
> From: rsyslog-bounces at lists.adiscon.com [mailto:rsyslog-
> bounces at lists.adiscon.com] On Behalf Of RB
> Sent: Friday, June 19, 2009 6:27 PM
> To: rsyslog-users
> Subject: Re: [rsyslog] memory alloc problems - any advise?
> 
> On Fri, Jun 19, 2009 at 10:14, Rainer Gerhards<rgerhards at hq.adiscon.com>
> wrote:
> > What is surprising is that the memory is not given back to the OS when
the
> > data has been processed. Well... I know that some data blocks may still
be
> > held and thus prevent giving memory back. But that should be solved when
a
> > few new messages come in. Still, nothing changes in that scenario. What
> > puzzles me even more is that when I start a new burst of messages (I send
> > around one million each), it looks like almost only new memory is
obtained
> > from the OS for them. At least here I had expected that the allocator
would
> > re-use what was already claimed.
> 
> Can you clarify what you mean by "not given back to the OS"?  Do you
> mean that the RSS of rsyslog remains the same, or that the system
> 'free' memory does not go back up, or something else entirely?  I'm
> wondering if you're seeing caching effects.

Rss remains the same, looks like sbrk() is not called. I poked somemore
around, and it looks like I need to do a malloc_trim() call in glibc to solve
this issue. Will post some stats soon...

Rainer