Re: disk performance benchmarks

Greg Stark <gsstark@mit.edu>

From: Greg Stark <gsstark@mit.edu>
To: pgsql-general@postgresql.org
Date: 2004-09-15T06:07:08Z
Lists: pgsql-performance, pgsql-general
Vivek Khera <khera@kcilink.com> writes:

> On Sep 14, 2004, at 9:49 PM, Joshua D. Drake wrote:
> 
> > It is my experience that RAID 5 is not that great for heavy write situations
> > and that RAID 10 is better.
> >
> It is my experience that this depends entirely on how many spindles you have in
> your RAID.  For 4 or 5 spindles, I find RAID10 faster.  With 14 spindles, it
> was more or less a toss-up for me.

I think this depends massively on the hardware involved and the applications
involved. 

For write heavy application I would expect RAID5 to be a lose on any
software-raid based solution. Only with good hardware raid systems with very
large battery-backed cache would it begin to be effective.

-- 
greg