From: Stan Hoeppner <stan@hardwarefreak.com>
To: Joe Landman <joe.landman@gmail.com>
Cc: xfs@oss.sgi.com, linux-raid <linux-raid@vger.kernel.org>
Subject: Re: very slow file deletion on an SSD
Date: Sat, 26 May 2012 14:56:54 -0500 [thread overview]
Message-ID: <4FC13586.8060408@hardwarefreak.com> (raw)
In-Reply-To: <4FBF60D1.80104@gmail.com>
On 5/25/2012 5:37 AM, Joe Landman wrote:
> Hi folks:
Hi Joe,
I may be all wet here, but this is the only thing that jumped out at me:
> meta-data=/dev/md20
> data = sunit=8 swidth=56 blks
> log =internal sunit=8 blks
8*56KB (or 7*64KB) = 448KB write out
> [root@siFlash ~]# mdadm --detail /dev/md20
> /dev/md20:
> Version : 1.2
> Raid Devices : 8
> Layout : left-symmetric
> Chunk Size : 32K
7*32KB = 224KB stripe size
> All this said, deletes from this unit are taking 1-2 seconds per file ...
> Anything obvious that we are doing wrong?
Other than your XFS writeout being apparently twice the size of your
RAID stripe, nothing else stands out that I can see. I'm not a block
layer expert. And since mkfs.xfs came up with 448KB, apparently this
should be fine. However, everything in the literature, and the experts
on this list, tells us to always precisely align XFS to the RAID stripe.
That doesn't seem to be the case here.
--
Stan
next prev parent reply other threads:[~2012-05-26 19:56 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-25 10:37 very slow file deletion on an SSD Joe Landman
2012-05-25 10:45 ` Bernd Schubert
2012-05-25 10:49 ` Joe Landman
2012-05-25 14:48 ` Roberto Spadim
2012-05-25 16:57 ` Ben Myers
2012-05-25 16:54 ` Joe Landman
2012-05-25 16:59 ` Christoph Hellwig
2012-05-26 16:00 ` David Brown
2012-05-26 19:56 ` Stan Hoeppner [this message]
2012-05-26 23:18 ` Dave Chinner
2012-05-26 23:25 ` Joe Landman
2012-05-27 0:07 ` Dave Chinner
2012-05-27 0:10 ` joe.landman
2012-05-27 1:49 ` Joe Landman
2012-05-27 2:40 ` Eric Sandeen
2012-05-27 2:43 ` Eric Sandeen
2012-05-27 7:34 ` Stefan Ring
2012-05-27 13:15 ` Krzysztof Adamski
2012-05-27 14:59 ` joe.landman
2012-05-27 16:07 ` Eric Sandeen
2012-05-27 17:14 ` Joe Landman
2012-05-27 17:17 ` Joe Landman
2012-05-26 23:55 ` Joe Landman
2012-05-27 0:07 ` Jon Nelson
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