From: John Robinson <john.robinson@anonymous.org.uk>
To: Stan Hoeppner <stan@hardwarefreak.com>
Cc: Simon Matthews <simon.d.matthews@gmail.com>,
Pol Hallen <raid1@fuckaround.org>,
linux-raid@vger.kernel.org
Subject: Re: standard performance (write speed 20Mb/s)
Date: Wed, 27 Jul 2011 11:26:39 +0100 [thread overview]
Message-ID: <4E2FE7DF.1020906@anonymous.org.uk> (raw)
In-Reply-To: <4E2FE6C9.4070604@hardwarefreak.com>
On 27/07/2011 11:22, Stan Hoeppner wrote:
> On 7/27/2011 12:42 AM, Simon Matthews wrote:
>> On Sun, Jul 17, 2011 at 5:11 AM, John Robinson
>> <john.robinson@anonymous.org.uk> wrote:
>>
>>> Pretty poor. CentOS 5, Intel ICH10, md RAID 6 over 5 7200rpm 1TB drives,
>>> then LVM, then ext3:
>>> # dd if=/dev/zero of=test bs=4096 count=262144
>>> 262144+0 records in
>>> 262144+0 records out
>>> 1073741824 bytes (1.1 GB) copied, 2.5253 seconds, 425 MB/s
>>
>> What hard drive offers a sustained data rate of 425 MB/s or even half that?
>
> 425 MB/s / 3 spindles = 142 MB/s per spindle
>
> That's not poor, it's excellent. Which drives are these? WD Black,
> Seagate, Hitachi?
Gentlemen, we've been round this loop before about 10 days ago. Pol's 20
MB/s was poor because he was testing on an array with unaligned
partitions and a resync was running, my 425 MB/s was a bad test because
it didn't use fdatasync or direct and I said dd was a bad test anyway,
etc etc.
Cheers,
John.
next prev parent reply other threads:[~2011-07-27 10:26 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-07-16 19:40 standard performance (write speed 20Mb/s) Pol Hallen
2011-07-17 4:26 ` Stan Hoeppner
2011-07-17 8:12 ` Pol Hallen
2011-07-17 12:11 ` John Robinson
2011-07-17 12:22 ` Iustin Pop
2011-07-17 12:51 ` John Robinson
2011-07-17 13:28 ` Iustin Pop
2011-07-18 9:04 ` John Robinson
2011-07-17 22:05 ` Stan Hoeppner
2011-07-27 5:42 ` Simon Matthews
2011-07-27 5:46 ` Roman Mamedov
2011-07-27 10:22 ` Stan Hoeppner
2011-07-27 10:26 ` John Robinson [this message]
2011-07-27 12:35 ` Joe Landman
2011-07-27 13:54 ` Stan Hoeppner
2011-07-17 23:03 ` Stan Hoeppner
2011-07-18 11:52 ` Pol Hallen
2011-07-21 17:07 ` standard performance (write speed ??Mb/s) - new raid5 array Pol Hallen
2011-07-22 0:05 ` Stan Hoeppner
2011-07-22 7:08 ` Pol Hallen
2011-07-22 8:13 ` Erwan Leroux
2011-07-17 16:48 ` standard performance (write speed 20Mb/s) Gordon Henderson
-- strict thread matches above, loose matches on Subject: below --
2011-07-18 12:03 Pol Hallen
2011-07-20 12:31 ` Stan Hoeppner
2011-07-20 20:02 ` Pol Hallen
[not found] ` <CADNH=7HR7euaWem0tpLxJfRe0hYnRP5fwxJ6MC5vJeNf=T=PzA@mail.gmail.com>
2011-07-21 0:02 ` Stan Hoeppner
2011-07-21 6:57 ` Mathias Burén
2011-07-21 8:55 ` Erwan Leroux
2011-07-21 15:06 ` Paweł Brodacki
2011-07-21 15:30 ` Erwan Leroux
2011-07-21 15:42 ` Erwan Leroux
2011-07-25 6:39 ` Paweł Brodacki
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