Re: With 4 disks should I go for RAID 5 or RAID 10

From: "Fernando Hevia" <fhevia(at)ip-tel(dot)com(dot)ar>
To: "'Mark Mielke'" <mark(at)mark(dot)mielke(dot)cc>
Cc: "'pgsql-performance'" <pgsql-performance(at)postgresql(dot)org>
Subject: Re: With 4 disks should I go for RAID 5 or RAID 10
Date: 2007-12-26 19:32:21
Message-ID: 0f8201c847f6$08e15090$8f01010a@iptel.com.ar
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

Mark Mielke Wrote:

>In my experience, software RAID 5 is horrible. Write performance can
>decrease below the speed of one disk on its own, and read performance will
>not be significantly more than RAID 1+0 as the number of stripes has only
>increased from 2 to 3, and if reading while writing, you will not get 3X as
>RAID 5 write requires at least two disks to be involved. I believe hardware
>RAID 5 is also horrible, but since the hardware hides it from the
>application, a hardware RAID 5 user might not care.

>Software RAID 1+0 works fine on Linux with 4 disks. This is the setup I use
>for my personal server.

I will use software RAID so RAID 1+0 seems to be the obvious choice.
Thanks for the advice!

In response to

Responses

Browse pgsql-performance by date

  From Date Subject
Next Message Jared Mauch 2007-12-26 20:22:30 pg_dump performance
Previous Message Fernando Hevia 2007-12-26 19:28:25 Re: With 4 disks should I go for RAID 5 or RAID 10