Re: [HACKERS] Fwd: Joins and links

Then <boekhold(at)tibco(dot)com> spoke up and said:
> Hannu Krosing wrote:
> > Leon wrote:
> > > Frankly, I didn't even consider fetching database from disk. This
> > > slows queries immensely and I wonder if there exist someone who
> > > doesn't keep their entire DB in RAM.
> >
> > Well, I personally dont even know, how I could keep my entire PostgreSQL
> > DB in RAM :)
>
> I thought about doing this once on a Linux box. What I was thinking about was
> creating a large RAM disk, and use that disk together with a physical drive in
> a mirror setup. However, I was never able to create a large enough RAM disk back then
> (must have been like LInux 2.0), and also the RAID mirror code wasn't able to
> support such a mix of devices (i.e. RAM disk + physical disk). The situation might
> have changed by now.

Maarten, PostgreSQL keeps it's data in the filesystem, rather than on
raw disks. Due to the nature of *nix, all you need to do to keep your
entire DB in memory is have enough memory. The buffer cache will do
the rest, for you. Of course, you still need to start it up with -F
to avoid fsync's. This is also somewhat OS dependent, as you may have
to do some tuning to allow full memory utilization in this manner.

--
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| After all, why else would it support only single inheritance?? |
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