Re: Quad processor options

-----Original Message-----
From: pgsql-performance-owner(at)postgresql(dot)org
[mailto:pgsql-performance-owner(at)postgresql(dot)org] On Behalf Of Bjoern Metzdorf
Sent: Tuesday, May 11, 2004 3:11 PM
To: scott.marlowe
Cc: pgsql-performance(at)postgresql(dot)org; Pgsql-Admin (E-mail)
Subject: Re: [PERFORM] Quad processor options

scott.marlowe wrote:
>>Next drives I'll buy will certainly be 15k scsi drives.
>
> Better to buy more 10k drives than fewer 15k drives. Other than slightly
> faster select times, the 15ks aren't really any faster.

Good to know. I'll remember that.

>>In peak times we can get up to 700-800 connections at the same time.
>>There are quite some updates involved, without having exact numbers I'll
>>think that we have about 70% selects and 30% updates/inserts.
>
> Wow, a lot of writes then.

Yes, it certainly could also be only 15-20% updates/inserts, but this is
also not negligible.

> Sure, adaptec makes one, so does lsi megaraid. Dell resells both of
> these, the PERC3DI and the PERC3DC are adaptec, then lsi in that order, I
> believe. We run the lsi megaraid with 64 megs battery backed cache.

The LSI sounds good.

> Intel also makes one, but I've heard nothing about it.

It could well be the ICP Vortex one, ICP was bought by Intel some time ago..

> I haven't directly tested anything but the adaptec and the lsi megaraid.
> Here at work we've had massive issues trying to get the adaptec cards
> configured and installed on, while the megaraid was a snap. Installed RH,

> installed the dkms rpm, installed the dkms enabled megaraid driver and
> rebooted. Literally, that's all it took.

I didn't hear anything about dkms for debian, so I will be hand-patching
as usual :)

Regards,
Bjoern

-------------------------

Personally I would stay away from anything intel over 2 processors. I have
done some research and if memory serves it something like this. Intel's
architecture makes each processor compete for bandwidth on the bus to the
ram. Amd differs in that each proc has its own bus to the ram.

Don't take this as god's honest fact but just keep it in mind when
considering a Xeon solution, it may be worth your time to do some deeper
research into this. There is some on this here
http://www4.tomshardware.com/cpu/20030422/

Rob