Re: Non-linear Performance - Mailing list pgsql-general

From Peter A. Daly
Subject Re: Non-linear Performance
Date
Msg-id 3CF642A4.7040908@ix.netcom.com
Whole thread Raw
In response to Non-linear Performance  (Curt Sampson <cjs@cynic.net>)
Responses Re: Non-linear Performance  (Bruce Momjian <pgman@candle.pha.pa.us>)
List pgsql-general
>
>
>>What is the most amount of SORT_MEM it makes sense to allocate?
>>
>
>I've never experimented with it, but certainly the standard default
>(512K = 0.5M) is pretty small for modern machines.  In a 2G machine
>I might try settings around 100M-500M to see what works best.  (Note
>this is just for a one-off btree creation --- for ordinary queries you
>need to allow for multiple sorts going on in parallel, which is one
>reason the default sort_mem is not very large.)
>
I will run some benchmarks and let the list know the results.  If this
can speed it up a large amount, I can get another 6 gig of RAM into this
machine which I hope can let me leave the SORT_MEM at a high enough
amount to speed up our huge nightly batch database reload.

It's a Dual Xeon 500Mhz Machine.

-Pete


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