Re: oom_killer

2011/4/21 Tory M Blue <tmblue(at)gmail(dot)com>:
> On Thu, Apr 21, 2011 at 7:27 AM, Merlin Moncure <mmoncure(at)gmail(dot)com> wrote:
>> On Thu, Apr 21, 2011 at 3:28 AM, Tory M Blue <tmblue(at)gmail(dot)com> wrote:
>
>>> Fedora 12
>>> 32gig memory, 8 proc
>>> postgres 8.4.4, slony 1.20
>>> 5 gigs of swap (never hit it!)
>>
>> curious: using 32/64 bit postgres? what are your postgresql.conf
>> memory settings?
>>
>> merlin
>>
>
> 32bit
> 32gb
> PAE kernel
>
> # - Checkpoints -
> checkpoint_segments = 100
> max_connections = 300
> shared_buffers = 2500MB       # min 128kB or max_connections*16kB
> max_prepared_transactions = 0
> work_mem = 100MB
> maintenance_work_mem = 128MB
> fsync = on
>

I didn't understand what value you set for vm.overcommit parameters.
Can you give it and the values in /proc/meminfo, the interesting one
are "Commit*" ?

If you have strict rules(overcommit=2), then your current kernel
config may need some love : the commit_limit is probably too low
because you have a small swap partition. One way is to change :
vm.overcommit_ratio.
By default it should be something like 21GB (0.5*32+5) of
commit_limit, and you probably want 32GB :)

Maybe you have some minor changes in your install or application usage
and you just hit the limit.

--
Cédric Villemain               2ndQuadrant
http://2ndQuadrant.fr/     PostgreSQL : Expertise, Formation et Support