Re: Mapping a database completly into Memory

>>>>> "TL" == Tom Lane <tgl@sss.pgh.pa.us> writes:

TL> Franco Bruno Borghesi <franco@akyasociados.com.ar> writes:
>> wouldn't also increasing shared_buffers to 64 or 128 MB be a good
>> performance improvement? This way, pages belonging to heavily used
>> indexes would be already cached by the database itself.

TL> Not necessarily.  The trouble with large shared_buffers settings is you
TL> end up with lots of pages being doubly cached (both in PG's buffers and

I think if you do a lot of inserting/updating to your table, then more
SHM is better (and very high fsm settings), since you defer pushing
out the dirty pages to the disk.  For read-mostly, I agree that
letting the OS do the caching is a better way.


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