CERC RAID5 performance lower than everyone else

[Paul M. Dyer]

Try setting the read-ahead buffer.   I find that helps some.

/sbin/blockdev --setra 8192 /dev/sda

Otherwise, switch to RAID-0 and you will really see an improvement.  Keep a backup.

Paul

----- Original Message -----
From: "Tino Schwarze" <linux-poweredge.lists at tisc.de>
To: linux-poweredge at dell.com
Sent: Friday, July 18, 2008 7:22:56 AM (GMT-0600) America/Chicago
Subject: Re: CERC RAID5 performance lower than everyone else

On Fri, Jul 18, 2008 at 01:07:13PM +0100, John Hodrien wrote:

> >> Sounds reasonable to me.  I gave up on RAID 5 and switched to RAID 1.  When
> >> the performance of that sucked I then dropped to software RAID 1.  That's got
> >> it up to a stunning 25Mbyte/sec write speed.
> >>
> >> The card is awful.
> >
> > I wonder how people dare to actually sell such crap! I mean, isn't there
> > some kind of engineer's ethics or something?!
> 
> They probably felt that anyone who bought a non-SCSI raid card at the time
> deserved all they got for being such cheapskates.

D'oh. Sounds bitterly reasonable. :-<

Tino, having suffered from slow MegaRAID SATA controller.

-- 
"What we nourish flourishes." - "Was wir nähren erblüht."

www.craniosacralzentrum.de
www.forteego.de

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