From: William Yu <wyu@talisys.com>
Subject: Re: Help specifying new web server/database machine
Date: Thu, 09 Jun 2005 12:53:38 -0700
Organization: Hub.Org Networking Services
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To: pgsql-performance@postgresql.org

Rory Campbell-Lange wrote:
> Processor:
> 
> First of all I noted that we were intending to use Opteron processors. I
> guess this isn't a straightforward choice because I believe Debian (our
> Linux of choice) doesn't have a stable AMD64 port. However some users on
> this list suggest that Opterons work very well even in a 32 bit
> environment. Some have suggested that a single dual core processor is
> the way to go. The RAM needs to fit the CPU arrangement too; William
> points out that one needs 2 DIMMS per CPU.


Your summary here just pointed out the obvious to me. Start with a 2P MB 
but only populate a single DC Opteron. That'll give you 2P system with 
room to expand to 4P in the future. Plus you only need to populate 1 
memory bank so you can do 2x1GB.

> Disks:
> 
> I'm somewhat confused here. I've followed the various notes about SATA
> vs SCSI and it seems that SCSI is the way to go. On a four-slot 1U
> server, would one do a single RAID10 over 4 disks 10000rpm U320 disks?
> I would run the database in its own partition, separate from the rest of
> the OS, possible on LVM. An LSI-Megaraid-2 appears to be the card of
> choice.

With only 4 disks, a MegaRAID U320-1 is good enough. It's quite a 
premium to go to the 2x channel MegaRAID. With 4 drives, I'd still do 2 
big drives mirrored for the DB partition and 2 small drives for OS+WAL.