All of lore.kernel.org
 help / color / mirror / Atom feed
From: Stan Hoeppner <stan@hardwarefreak.com>
To: Stefan Ring <stefanrin@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>, xfs@oss.sgi.com
Subject: Re: XFS: Abysmal write performance because of excessive seeking (allocation groups to blame?)
Date: Tue, 10 Apr 2012 15:44:30 -0500	[thread overview]
Message-ID: <4F849BAE.6070901@hardwarefreak.com> (raw)
In-Reply-To: <CAAxjCEzRa7CpbA9iESEDjmWQMsJTjkWHJj69ADOXDa4CiRpx3w@mail.gmail.com>

On 4/10/2012 9:02 AM, Stefan Ring wrote:
>> And is XFS aligned to the RAID 6?
>>
>> What does xfs_info display on it?
> 
> Yes, it’s aligned.
> 
> meta-data=/dev/mapper/vg_data-lvhome 

Is the LVM volume aligned to the RAID stripe?  Is their a partition atop
the RAID LUN and under LVM?  Is the partition aligned?  Why LVM anyway?

>                                  isize=256    agcount=4, agsize=73233656 blks
>          =                       sectsz=512   attr=2
> data     =                       bsize=4096   blocks=292934624, imaxpct=5
>          =                       sunit=8      swidth=32 blks
> naming   =version 2              bsize=4096   ascii-ci=0
> log      =internal               bsize=4096   blocks=143040, version=2
>          =                       sectsz=512   sunit=8 blks, lazy-count=1
> realtime =none                   extsz=4096   blocks=0, rtextents=0
> 
> I changed the stripe size to 32kb in the meantime. This way, it
> performs slightly better.

The devil is always in the details.  Were you using partitions and LVM
with the RAID1 concat tesing?  With the free space testing?

I assumed you were directly formatting the LUN with XFS.  With LVM and
possibly partitions involved here, that could explain some of the
mediocre performance across the board, with both EXT4 and XFS.  If one
wants maximum performance from their filesystem, one should typically
stay away from partitions and LVM, and any other layers that can slow IO
down.

-- 
Stan

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

  parent reply	other threads:[~2012-04-10 20:44 UTC|newest]

Thread overview: 64+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-04-05 18:10 XFS: Abysmal write performance because of excessive seeking (allocation groups to blame?) Stefan Ring
2012-04-05 19:56 ` Peter Grandi
2012-04-05 22:41   ` Peter Grandi
2012-04-06 14:36   ` Peter Grandi
2012-04-06 15:37     ` Stefan Ring
2012-04-07 13:33       ` Peter Grandi
2012-04-05 21:37 ` Christoph Hellwig
2012-04-06  1:09   ` Peter Grandi
2012-04-06  8:25   ` Stefan Ring
2012-04-07 18:57     ` Martin Steigerwald
2012-04-10 14:02       ` Stefan Ring
2012-04-10 14:32         ` Joe Landman
2012-04-10 15:56           ` Stefan Ring
2012-04-10 18:13         ` Martin Steigerwald
2012-04-10 20:44         ` Stan Hoeppner [this message]
2012-04-10 21:00           ` Stefan Ring
2012-04-05 22:32 ` Roger Willcocks
2012-04-06  7:11   ` Stefan Ring
2012-04-06  8:24     ` Stefan Ring
2012-04-05 23:07 ` Peter Grandi
2012-04-06  0:13   ` Peter Grandi
2012-04-06  7:27     ` Stefan Ring
2012-04-06 23:28       ` Stan Hoeppner
2012-04-07  7:27         ` Stefan Ring
2012-04-07  8:53           ` Emmanuel Florac
2012-04-07 14:57           ` Stan Hoeppner
2012-04-09 11:02             ` Stefan Ring
2012-04-09 12:48               ` Emmanuel Florac
2012-04-09 12:53                 ` Stefan Ring
2012-04-09 13:03                   ` Emmanuel Florac
2012-04-09 23:38               ` Stan Hoeppner
2012-04-10  6:11                 ` Stefan Ring
2012-04-10 20:29                   ` Stan Hoeppner
2012-04-10 20:43                     ` Stefan Ring
2012-04-10 21:29                       ` Stan Hoeppner
2012-04-09  0:19           ` Dave Chinner
2012-04-09 11:39             ` Emmanuel Florac
2012-04-09 21:47               ` Dave Chinner
2012-04-07  8:49         ` Emmanuel Florac
2012-04-08 20:33           ` Stan Hoeppner
2012-04-08 21:45             ` Emmanuel Florac
2012-04-09  5:27               ` Stan Hoeppner
2012-04-09 12:45                 ` Emmanuel Florac
2012-04-13 19:36                   ` Stefan Ring
2012-04-14  7:32                     ` Stan Hoeppner
2012-04-14 11:30                       ` Stefan Ring
2012-04-09 14:21         ` Geoffrey Wehrman
2012-04-10 19:30           ` Stan Hoeppner
2012-04-11 22:19             ` Geoffrey Wehrman
2012-04-07 16:50       ` Peter Grandi
2012-04-07 17:10         ` Joe Landman
2012-04-08 21:42           ` Stan Hoeppner
2012-04-09  5:13             ` Stan Hoeppner
2012-04-09 11:52               ` Stefan Ring
2012-04-10  7:34                 ` Stan Hoeppner
2012-04-10 13:59                   ` Stefan Ring
2012-04-09  9:23             ` Stefan Ring
2012-04-09 23:06               ` Stan Hoeppner
2012-04-06  0:53   ` Peter Grandi
2012-04-06  7:32     ` Stefan Ring
2012-04-06  5:53   ` Stefan Ring
2012-04-06 15:35     ` Peter Grandi
2012-04-10 14:05       ` Stefan Ring
2012-04-07 19:11     ` Peter Grandi

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4F849BAE.6070901@hardwarefreak.com \
    --to=stan@hardwarefreak.com \
    --cc=hch@infradead.org \
    --cc=stefanrin@gmail.com \
    --cc=xfs@oss.sgi.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.