Re: Hardware estimation

On 5 Nov 2002, Vidal wrote:

> Hi,
>
> I am a first timer in this forum. We have an application using
> Postgre Database with a considerable growth expected for the next
> year. We are facing some dificulties to estimate the equipment we´ll
> need and I would like to exchange ideas about:
>
> - hardware estimation
> - performance concerns
>
> with anyone that faced Postgre applications with more than 150Gb.
>
> I am talking about a database that will achieve:
>
> - 200Gb total space
> - 2 major space cosuming tables (400 million and 50 million tuples)
> - major system process - batch process reading from and writing to
> text files (telephony records) - aprox 2 million records processed
> (read or written every day)
>
> Operating System : Linux
>
> Equipment we are planning:
> - IBM xSeries 255 4 Intel Xeon 1.5GHz, MP, 512KB Cache, 2GB RAM,
> External Storage System(IBM SSA)

Are you going to be supporting a fair number of simo users, or is this
gonna be mostly a single batch at a time operation?

If you're mostly gonna be running single user batch files for all the
heavy lifting, save the money you'd spend on a quad Xeon and spend it on
more / bigger / faster drive arrays and faster individual CPUs, like a
dual Athlon 2800.

But maybe the multi-user part is still very important to your uses. If
so...

If you are looking at a quad Xeon, then take a look at going all the way
to 64 bit architecture (Ultra Sparc, HP, P6xx IBM, Itanium 2) where you
can throw scads of memory at your problems and postgresql can access it.

You might find a dual Ultra Sparc will outrun the quad xeon due to better
memory access, larger caches (8Meg L2 cache), and being able to put
ungodly amounts of memory into the machine.

Some of the "low end" 64 bit machines are not any more expensive than a
quad xeon can run.

A quad 1GHz Power4 with 8 gig ram, dual 36 Gig drives and all the fixings
goes for $44,000. That's with 64 Meg L3 cache.