[Re: [lug] Memory problem]

[John Hernandez]

I use 'top' to get insight into problems like these.  No X required. 
'M' sorts processes by memory usage (at least on newer versions), hogs
at the top of the list.  Are you having performance problems?  The
reason I ask is that it's quite normal for Linux (and OS kernels in
general) to find equilibrium at a point where most of the physical RAM
is used.  Excessive paging/swapping is really what hurts performance. 
On my perfectly responsive and fairly happy box (running two typical
bloated offenders), I see:

Mem:   128204K av,  125580K used,    2624K free,   62548K shrd,    2796K
buff
Swap:  265032K av,   29948K used,  235084K free                   18380K
cached

  PID USER     PRI  NI  SIZE  RSS SHARE STAT  LIB %CPU %MEM   TIME
COMMAND
 8643 me         2   0 82140  54M  6028 S       0  0.0 43.7  11:10
netscape-com
 8576 root       9   0 52412  49M  2700 S       0  0.0 39.6   6:30 X

Anyone running Netscape 6 (full blown Communicator) or a recent Mozilla
on a 2.2 kernel?  How do they behave, particularly wrt memory footprint?

Justin wrote:
> 
> Hrmm, that could be the problem, and it was just a couple weeks ago since the
> counterstrike 1.0 server release. I can test it by rebooting the box once more
> to clear the memory and I just won't run the CS server for a while and see
> what happens. Thanks.
> 
> Justin
> 
> Shannon Johnston <nunar at iws.net> wrote:
> > I noticed you're running CounterStrike. According to the hlds_l mailing
> > list, the newer version of the hlds_l has a pretty severe memory leak.
> > It's behaving a lot like you're describing. (lots of mem usage with no
> > obvious casue.)
> >
> > Shannon Johnston
> >
> > On Tue, 28 Nov 2000, D. Stimits wrote:
> >
> > > Justin wrote:
> > > >
> > > > I'm running into a memory issue on my main server machine. I have never
> had
> > > > this problem before and it seemed to start within the last 2 weeks.
> Using
> > > > procinfo I am seeing the memory usage gradually increasing until it
> reaches
> > > > the max of 128megs. Last week I started killing off process's randomly
> to see
> > > > if that free'd memory but no luck. I tried restarting all my main server
> apps
> > > > including apache, postfix, identd, syslog, inetd, and some others. The
> memory
> > > > usage still showed the same, but when doing a ps aux none of the
> process's
> > > > seemed to be hogging any memory. I ended up shutting down and booting
> back up
> > > > to clear the memory problem. After the reboot the mem usage, according
> to
> > > > procinfo, was about 50megs. After my users had started up all their
> stuff
> > > > again the memory was up to about 90megs, which is normal. I ran my
> > > > counterstrike server for a while saturday night, which consumes about
> 28megs,
> > > > then shut it down later on. The memory dropped back down to around
> 90megs
> > > > after that but has been increasing daily for no particular reason. It's
> now at
> > > > about 122megs of the max 128, and the only thing I've done since the
> weekend
> > > > was update my BIND to P7. Any way to trouble shoot this or any ideas of
> what
> > > > might be going on? The box is Redhat 6.1 (updated) w/ kernel 2.2.15.
> Thanks in
> > > > advance for any help.
> > > >
> > > > Justin
> > > >
> > >
> > > Sometimes, depending on how you are measuring the memory use, the
> > > meassurements can be deceptive. Released memory will sometimes not be
> > > simply released, but will instead end up cached. And if you are running
> > > an X server, your video card memory can be measured as part of the
> > > system ram...if it has 32 megs and the system 128, you could see up to
> > > 160 megs in use. One thing I'd suggest is using a tool that
> > > distinguishes between just ram used, and cache. Try xosview if you can.
> > >
> > > If it turns out that you do have memory being used up, it's possible
> > > that one of your apps has a memory leak. Sometimes a restart mechanism
> > > to a daemon does not actually kill the app, but simply tells it to
> > > re-read its init files; if this is the case, memory won't go down after
> > > a restart. Try a full stop and stop.
> > >

-- 

John Hernandez, Network Engineer --------------------------------------
US Department of Commerce                             tel: 303-497-6392
NOAA/OAR - Mailstop R/OM12                            fax: 303-497-6005
325 Broadway                            e-mail: John.Hernandez at noaa.gov
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