Mikko Partio wrote:

Isn't 128MB quite low considering the "current standard" of 25% - 50% of total ram?

I had also read a statement about using this amount of memory as shared buffers. Exactly that was the reason why I set it to such a high value, but I am now convinced that this is wrong.

http://www.varlena.com/varlena/GeneralBits/Tidbits/perf.html#shbuf
and
http://www.varlena.com/varlena/GeneralBits/Tidbits/annotated_conf_e.html
are quite clear about this.

On the other hand, http://edoceo.com/liber/db-postgresql-performance.php says:

Shared Memory

PostgreSQL uses lots of this, view ipcs to prove it, the more shared memory the better as more data (tables) can be loaded. On a dedicated datbase server it's not uncommon to give half the memory to the database.

and

shared_buffers = N

Set anywhere from 1/4 to 1/2 physical memory, must set kernel shared memory max first. Will see noticeable difference.

Since the first links are also mentioned on the official PostgreSQL website (http://www.postgresql.org/docs/techdocs.2) I think they should be trusted more.

Regards,
Christian

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