RHEL3 swapping too much (was Re: Monitoring Memory)

[Christopher McCrory <chrismcc pricegrabber com>]

Hello...

On Thu, 2004-06-10 at 09:54, Kevin Stussman wrote:
> Yeah, we're looking into this vm option...Did you find it to help the
> system swap less?
> 

Yes

On dual P4 3.2Ghz zeon w/ 4 gig ram only running apache with a 30M
footprint we were _swapping out apache_ .  The only meaningful ($$$)
process was being swapped!  $# %!$#

On RH7.3 turning off swap worked fine, on RHEL3 turning off swap seems
to increase load. ? ? ?



> Found these to be helpful as well. 
> 
> http://www.redhat.com/advice/tips/meminfo.html
> http://www.redhat.com/whitepapers/rhel/OracleonLinux.pdf
> https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=118706
> https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=124576
> 
> Regards,
> 
> Kevin
> 
> 
> On Wed, 2004-06-09 at 18:21, Christopher McCrory wrote:
> > On Wed, 2004-06-09 at 16:46, Kevin Stussman wrote:
> > > I have been looking at /proc/meminfo and /proc/slabinfo trying to figure
> > > out what is meaning to a swapping problem that we are experiencing. It
> > > seems like we have tons of cache memory, but when new memory is needed
> > > the OS starts to swap.
> > > 
> > 
> > https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=89226
> > 
> > 
> > [chrismcc@ chrismcc]$  tail /etc/sysctl.conf
> >  
> > # Controls whether core dumps will append the PID to the core filename.
> > # Useful for debugging multi-threaded applications.
> > kernel.core_uses_pid = 1
> > # "Just In Case", reboot on panic
> > kernel.panic = 1
> >  
> > # temporary
> >  
> > vm.pagecache = 1 10 20
> > 
> > 
> > 
> > 
> > > By using the meminfo and slabinfo, what are some meaningful values to be
> > > monitoring? I'm trying to make some sense of how things add up but i'm
> > > not having much luck beyond the basics. For example, I would have
> > > thought that (Inactive + Active + Free) = Total or something like that,
> > > but no (these values will end up on a graph in cacti).
> > > 
> > > The documentation for the fields in meminfo and slabinfo is not very
> > > good and for this monitoring tool, I cannot use sar or free (it has to
> > > be file based hence /proc).
> > > 
> > > Regards,
> > > 
> > > Kevin.
> > > 
> > > --------------
> > > 
> > >         total:    used:    free:  shared: buffers:  cached:
> > > Mem:  6208667648 6173192192 35475456        0 66961408 5790060544
> > > Swap: 8587108352 265879552 8321228800
> > > MemTotal:      6063152 kB
> > > MemFree:         34644 kB
> > > MemShared:           0 kB
> > > Buffers:         65392 kB
> > > Cached:        5552276 kB
> > > SwapCached:     102080 kB
> > > Active:        4612504 kB
> > > ActiveAnon:    2542240 kB
> > > ActiveCache:   2070264 kB
> > > Inact_dirty:    892520 kB
> > > Inact_laundry:  140268 kB
> > > Inact_clean:    127828 kB
> > > Inact_target:  1154624 kB
> > > HighTotal:     5242816 kB
> > > HighFree:        16132 kB
> > > LowTotal:       820336 kB
> > > LowFree:         18512 kB
> > > SwapTotal:     8385848 kB
> > > SwapFree:      8126200 kB
> > > HugePages_Total:     0
> > > HugePages_Free:      0
> > > Hugepagesize:     2048 kB
> > > 
> > > 
> > > 
> > > --
> > > Taroon-list mailing list
> > > Taroon-list redhat com
> > > http://www.redhat.com/mailman/listinfo/taroon-list
-- 
Christopher McCrory
 "The guy that keeps the servers running"
 
chrismcc pricegrabber com
 http://www.pricegrabber.com
 
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