From: Roman Mamedov <rm@romanrm.ru>
To: "Mathias Burén" <mathias.buren@gmail.com>
Cc: Linux-RAID <linux-raid@vger.kernel.org>
Subject: Re: Performance question, RAID5
Date: Sun, 30 Jan 2011 04:57:06 +0500 [thread overview]
Message-ID: <20110130045706.4e8d6fa2@natsu> (raw)
In-Reply-To: <AANLkTi=ii-iLybJBS8ncajwXWZnkwLY=u0AcQiBJKPUf@mail.gmail.com>
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On Sat, 29 Jan 2011 23:44:01 +0000
Mathias Burén <mathias.buren@gmail.com> wrote:
> Controller device @ pci0000:00/0000:00:16.0/0000:05:00.0 [sata_mv]
> SCSI storage controller: HighPoint Technologies, Inc. RocketRAID
> 230x 4 Port SATA-II Controller (rev 02)
> host6: [Empty]
> host7: /dev/sde ATA SAMSUNG HD204UI {SN: S2HGJ1RZ800964 }
> host8: /dev/sdf ATA WDC WD20EARS-00M {SN: WD-WCAZA1000331}
> host9: /dev/sdg ATA SAMSUNG HD204UI {SN: S2HGJ1RZ800850 }
Does this controller support PCI-E 2.0? I doubt it.
Does you Atom mainboard support PCI-E 2.0? I highly doubt it.
And if PCI-E 1.0/1.1 is used, these last 3 drives are limited to 250 MB/sec.
in total, which in reality will be closer to 200 MB/sec.
> It's all SATA 3Gbs. OK, so from what you're saying I should see
> significantly better results on a better CPU? The HDDs should be able
> to push 80MB/s (read or write), and that should yield at least 5*80 =
> 400MB/s (-1 for parity) on easy (sequential?) reads.
According to the hdparm benchmark, your CPU can not read faster than 640
MB/sec from _RAM_, and that's just plain easy linear data from a buffer. So it
is perhaps not promising with regard to whether you will get 400MB/sec reading
from RAID6 (with all the corresponding overheads) or not.
--
With respect,
Roman
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next prev parent reply other threads:[~2011-01-29 23:57 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-01-29 22:48 Performance question, RAID5 Mathias Burén
2011-01-29 22:53 ` Roman Mamedov
2011-01-29 23:44 ` Mathias Burén
2011-01-29 23:57 ` Roman Mamedov [this message]
2011-01-30 0:15 ` Stan Hoeppner
2011-01-30 0:33 ` Mathias Burén
2011-01-30 0:27 ` Mathias Burén
2011-01-30 1:52 ` Keld Jørn Simonsen
2011-01-30 1:54 ` Mathias Burén
2011-01-30 5:56 ` Keld Jørn Simonsen
2011-01-30 12:12 ` Mathias Burén
2011-01-30 19:44 ` Stan Hoeppner
2011-01-30 19:46 ` Mathias Burén
2011-02-01 11:37 ` John Robinson
2011-02-01 13:53 ` Roberto Spadim
2011-02-01 14:02 ` Mathias Burén
2011-02-01 14:32 ` Roberto Spadim
2011-01-29 23:26 ` CoolCold
2011-01-30 0:18 ` Mathias Burén
2011-01-30 4:44 ` Roman Mamedov
2011-01-30 12:09 ` Mathias Burén
2011-01-30 12:15 ` Roman Mamedov
2011-01-30 19:41 ` Mathias Burén
2011-01-30 19:54 ` Roman Mamedov
2011-01-30 19:58 ` Mathias Burén
2011-01-30 20:03 ` Stan Hoeppner
2011-01-30 21:43 ` Mathias Burén
2011-01-31 3:39 ` Stan Hoeppner
2011-01-31 3:54 ` Roberto Spadim
2011-01-31 8:52 ` Keld Jørn Simonsen
2011-01-31 9:37 ` Mathias Burén
2011-01-31 13:11 ` Keld Jørn Simonsen
2011-01-31 14:43 ` Roberto Spadim
2011-01-31 18:44 ` Keld Jørn Simonsen
2011-01-31 20:42 ` NeilBrown
2011-01-31 21:41 ` Keld Jørn Simonsen
2011-01-31 21:43 ` Roberto Spadim
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