Re: First set of OSDL Shared Mem scalability results, some

Jan Wieck <janwieck@yahoo.com>

From: Jan Wieck <JanWieck@Yahoo.com>
To: Greg Stark <gsstark@mit.edu>
Cc: Christopher Browne <cbbrowne@acm.org>, pgsql-performance@postgresql.org
Date: 2004-10-14T04:29:19Z
Lists: pgsql-hackers, pgsql-performance
On 10/14/2004 12:22 AM, Greg Stark wrote:

> Jan Wieck <JanWieck@Yahoo.com> writes:
> 
>> Which would require that shared memory is not allowed to be swapped out, and
>> that is allowed in Linux by default IIRC, not to completely distort the entire
>> test.
> 
> Well if it's getting swapped out then it's clearly not being used effectively.

Is it really that easy if 3 different cache algorithms (PG cache, kernel 
buffers and swapping) are competing for the same chips?


Jan

> 
> There are APIs to bar swapping out pages and the tests could be run without
> swap. I suggested it only as an experiment though, there are lots of details
> between here and having it be a good configuration for production use.
> 


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