From: Steve Cousins <steve.cousins@maine.edu>
To: mark delfman <markdelfman@googlemail.com>
Cc: linux-raid <linux-raid@vger.kernel.org>
Subject: Re: MD write performance issue - found Catalyst patches
Date: Wed, 04 Nov 2009 14:05:45 -0500 [thread overview]
Message-ID: <4AF1D089.5080901@maine.edu> (raw)
In-Reply-To: <66781b10911040915t11a7f0c2td6a9ed5672935efb@mail.gmail.com>
mark delfman wrote:
> Some FS comparisons attached in pdf
>
> not sure what to make of them as yet, but worth posting
>
I'm not sure either. Two things jump out.
1. Why is raw RAID0 read performance slower than write performance
2. Why is read performance with some file systems at or above raw
read performance?
For number one, does this indicate that write caching is actually On on
the drives?
Are all tests truly apples-apples comparisons or were there other
factors in there that aren't listed in the charts?
I guess these issues might not have a lot to do with your main question
but you might want to double-check the tests and numbers.
Steve
next prev parent reply other threads:[~2009-11-04 19:05 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-10-18 10:00 MD write performance issue - found Catalyst patches mark delfman
2009-10-18 22:39 ` NeilBrown
2009-10-29 6:41 ` Neil Brown
2009-10-29 6:48 ` Thomas Fjellstrom
2009-10-29 7:32 ` Thomas Fjellstrom
2009-10-29 8:08 ` Asdo
2009-10-31 10:51 ` mark delfman
2009-11-03 4:58 ` Neil Brown
2009-11-03 12:11 ` mark delfman
2009-11-04 17:15 ` mark delfman
2009-11-04 17:25 ` Asdo
[not found] ` <66781b10911050904m407d14d6t7d3bec12578d6500@mail.gmail.com>
2009-11-05 19:09 ` Asdo
2009-11-06 4:52 ` Neil Brown
2009-11-06 10:28 ` Asdo
2009-11-06 10:51 ` Neil F Brown
2009-11-06 15:51 ` mark delfman
2009-11-04 19:05 ` Steve Cousins [this message]
2009-11-04 22:08 ` mark delfman
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