Re: Non-linear Performance

Peter A. Daly wrote:
> >
> >
> >>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.

I am curious how you are going to address >4 gig of RAM on a 32-bit
system, especially if you want to address it all from the same process.

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