Re: Linux mis-reporting memory

On Sep 21, 2007, at 4:43 AM, Gregory Stark wrote:
> "Csaba Nagy" <nagy(at)ecircle-ag(dot)com> writes:
>
>> On Fri, 2007-09-21 at 09:03 +0100, Gregory Stark wrote:
>>>>> Mem: 32945280k total, 32871832k used, 73448k free,
>>>>> 247432k buffers
>>>>> Swap: 1951888k total, 42308k used, 1909580k free,
>>>>> 30294300k cached
>>>>
>>> It seems to imply Linux is paging out sysV shared memory. In fact
>>> some of
>>> Heikki's tests here showed that Linux would do precisely that.
>>
>> But then why is it not reporting that in the "Swap: used"
>> section ? It
>> only reports 42308k used swap.
>
> Hm, good point.
>
> The other possibility is that Postgres just hasn't even touched a
> large part
> of its shared buffers.

Sorry for the late reply...

No, this is on a very active database server; the working set is
almost certainly larger than memory (probably by a fair margin :( ),
and all of the shared buffers should be in use.

I'm leaning towards "top on linux == dumb".
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Give your computer some brain candy! www.distributed.net Team #1828