Message-ID: <4DE0CB33.5060703@catalyst.net.nz>
Date: Sat, 28 May 2011 22:15:15 +1200
From: Mark Kirkwood <mark.kirkwood@catalyst.net.nz>
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CC: Kevin Grittner <Kevin.Grittner@wicourts.gov>,
	Greg Smith <greg@2ndquadrant.com>,
	postgres performance list <pgsql-performance@postgresql.org>
Subject: Re: serveRAID M5014 SAS
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On 28/05/11 21:42, Grzegorz Jaśkiewicz wrote:
> Yeah, I got it Mark.
>
> Unfortunately my current management decided to suspend that
> investigation for a while, so I can't get any tests done or anything
> like that.
>
> However we found out that another server we have shows similar issues.
> The same card, slightly different motherboard and completely different
> disks.
> The basic issue is around concurrent reads and writes. The card is
> ok-ish when one process hammers the disks, but as soon as it is
> multiple ones - it just blows (and I use it as a technical term ;) ).
> Still, with only one process reading/writing - the raid card sucks big
> time performance wise.
>

Sorry, Grzegorz I didn't mean to suggest you were not listening, I meant 
to ask if you could run the megaraid cli command to see if it showed up 
a battery!

If/when your management decide to let you look at this again, I'll be 
happy to help if I can!

Best wishes

Mark