Re: RAID Configuration Sugestion

From: Ron
Subject: Re: RAID Configuration Sugestion
Date: ,
Msg-id: 6.2.3.4.0.20050830103240.0219b640@pop.earthlink.net
(view: Whole thread, Raw)
In response to: RAID Configuration Sugestion  (Alvaro Nunes Melo)
Responses: Re: RAID Configuration Sugestion  ("Joshua D. Drake")
List: pgsql-performance

Tree view

RAID Configuration Sugestion  (Alvaro Nunes Melo, )
 Re: RAID Configuration Sugestion  (Bruno Wolff III, )
 Re: RAID Configuration Sugestion  (Bruno Wolff III, )
  Re: RAID Configuration Sugestion  (Matthew Nuzum, )
 Re: RAID Configuration Sugestion  (Ron, )
  Re: RAID Configuration Sugestion  ("Joshua D. Drake", )
   Re: RAID Configuration Sugestion  (Ron, )
    Re: RAID Configuration Sugestion  (Matthew Nuzum, )
    Re: RAID Configuration Sugestion  ("Joshua D. Drake", )
     Re: RAID Configuration Sugestion  (Ron, )
      Re: RAID Configuration Sugestion  (Michael Stone, )
       Re: RAID Configuration Sugestion  (Ron, )
        Re: RAID Configuration Sugestion  (Michael Stone, )
         Re: RAID Configuration Sugestion  (Ron, )

At 08:37 AM 8/30/2005, Alvaro Nunes Melo wrote:
>Hello,
>
>We are about to install a new PostgreSQL server, and despite of
>being a very humble configuration compared to the ones we see in the
>list, it's the biggest one we've got till now.
>
>The server is a Dual Xeon 3.0 with 2 GB RAM and two SCSI disks. Our
>main doubt is what is the best configuration for the disks. We are
>thinking about use them in a RAID-0 array. Is this the best option?
>What do you suggest on partitioning? Separate partitions for the OS,
>data and pg_xlog?

This is _very_ modest HW.  Unless your DB and/or DB load is similarly
modest, you are not going to be happy with the performance of your DBMS.

At a minimum, for safety reasons you want 4 HDs: 2 for a RAID 1 set
for the DB, and 2 for a RAID 1 set for the OS + pg_xlog.
2 extra HDs, even SCSI HDs, is cheap.  Especially when compared to
the cost of corrupted or lost data.

HD's and RAM are cheap enough that you should be able to upgrade in
more ways, but do at least that "upgrade"!

Beyond that, the best ways to spend you limited $ are highly
dependent on your exact DB and its usage pattern.

Ron Peacetree




pgsql-performance by date:

From: mudfoot@rawbw.com
Date:
Subject: Re: High load and iowait but no disk access
From: Markus Benne
Date:
Subject: When to do a vacuum for highly active table