From: keld@keldix.com
To: Charles Polisher <cpolish@surewest.net>
Cc: Peter Rabbitson <rabbit+list@rabbit.us>,
Phil Turmel <philip@turmel.org>,
linux-raid@vger.kernel.org
Subject: Re: Suboptimal raid6 linear read speed
Date: Wed, 16 Jan 2013 10:36:51 +0100 [thread overview]
Message-ID: <20130116093651.GB1069@www5.open-std.org> (raw)
In-Reply-To: <20130116044335.GA10165@kevin>
Hi Charles
It really does not show below which layout you use for RAID10. This is quite
important as the different layouts of RAID10 have quite different
performance characteristics. The 'far' layout tends to be the fastest.
Which command did you use to create the RAID10 array?
best regards
Keld
On Tue, Jan 15, 2013 at 08:43:35PM -0800, Charles Polisher wrote:
> keld@keldix.com wrote:
> > > Advantage Advantage
> > > vs 4 drives vs RAID0
> > > Config Drives Seq write Seq read Write Read Write Read
> > > ------ ------ ---------- ---------- ----- ----- ---- ----
> > > RAID0 4 8.1MB/sec 9.3MB/sec 1.00 1.00 1.00 1.00
> > > RAID0 8 16.8MB/sec 15.0MB/sec 2.07 1.61 1.00 1.00
> > >
> > > RAID1 4 2.1MB/sec 3.6MB/sec 1.00 1.00 0.25 0.38
> > > RAID1 8 1.6MB/sec 3.6MB/sec 0.76 1.00 0.09 0.24
> > >
> > > RAID5 4 16.8MB/sec 9.1MB/sec 1.00 1.00 2.07 0.97
> > > RAID5 8 17.2MB/sec 14.9MB/sec 1.02 1.63 2.12 1.60
> > >
> > > RAID6 4 12.6MB/sec 7.9MB/sec 1.00 1.00 1.55 0.84
> > > RAID6 8 14.4MB/sec 14.5MB/sec 1.63 1.83 1.77 1.55
> > >
> > > RAID10 4 4.0MB/sec 7.3MB/sec 1.00 1.00 0.49 0.78
> > > RAID10 8 6.3MB/sec 13.4MB/sec 1.57 1.83 0.37 0.89
> > >
> > What layout are you using for RAID10?
> > Is it Linux MD RAID10?
>
> # cat /proc/mdstat
> Personalities : [linear] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4] [multipath]
> md1 : active raid10 sdi[7] sdh[6] sdg[5] sdf[4] sde[3] sdd[2] sdc[1] sdb[0]
> 2118656 blocks 64K chunks 2 near-copies [8/8] [UUUUUUUU]
>
>
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next prev parent reply other threads:[~2013-01-16 9:36 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-01-15 12:33 Suboptimal raid6 linear read speed Peter Rabbitson
2013-01-15 12:45 ` Mikael Abrahamsson
2013-01-15 12:56 ` Peter Rabbitson
2013-01-15 16:13 ` Mikael Abrahamsson
2013-01-15 12:49 ` Phil Turmel
2013-01-15 12:55 ` Peter Rabbitson
2013-01-15 17:09 ` Charles Polisher
2013-01-15 19:57 ` keld
2013-01-16 4:43 ` Charles Polisher
2013-01-16 6:37 ` Tommy Apel Hansen
2013-01-16 9:36 ` keld [this message]
2013-01-16 16:09 ` Charles Polisher
2013-01-16 20:40 ` EJ Vincent
2013-01-15 23:17 ` Phil Turmel
2013-01-16 2:48 ` Stan Hoeppner
2013-01-16 2:58 ` Peter Rabbitson
2013-01-16 20:29 ` Stan Hoeppner
2013-01-16 21:20 ` Roy Sigurd Karlsbakk
2013-01-17 15:51 ` Mikael Abrahamsson
2013-01-18 8:31 ` Stan Hoeppner
2013-01-18 9:18 ` Mikael Abrahamsson
2013-01-18 22:56 ` Stan Hoeppner
2013-01-19 7:43 ` Mikael Abrahamsson
2013-01-19 22:48 ` Stan Hoeppner
2013-01-19 23:51 ` Maarten
2013-01-20 0:16 ` Chris Murphy
2013-01-20 0:49 ` Maarten
2013-01-20 1:37 ` Phil Turmel
2013-01-20 9:44 ` Chris Murphy
2013-01-20 6:26 ` Mikael Abrahamsson
2013-01-20 9:39 ` Chris Murphy
2013-01-20 16:55 ` Mikael Abrahamsson
2013-01-20 17:15 ` Chris Murphy
2013-01-20 17:17 ` Mikael Abrahamsson
2013-01-20 17:20 ` Chris Murphy
2013-01-19 23:53 ` Phil Turmel
2013-01-20 9:04 ` Wolfgang Denk
2013-01-20 19:28 ` Peter Grandi
2013-01-20 21:09 ` Mikael Abrahamsson
2013-01-20 21:50 ` Peter Grandi
2013-01-21 5:24 ` Mikael Abrahamsson
2013-01-21 14:40 ` Peter Rabbitson
2013-01-21 20:32 ` Peter Grandi
2013-01-21 20:55 ` Peter Grandi
2013-01-21 22:00 ` Peter Grandi
2013-01-19 13:21 ` Roy Sigurd Karlsbakk
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