From: Stan Hoeppner <stan@hardwarefreak.com>
To: Maurice Hilarius <maurice@harddata.com>,
Linux RAID <linux-raid@vger.kernel.org>
Subject: Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users
Date: Sun, 23 Jan 2011 19:52:57 -0600 [thread overview]
Message-ID: <4D3CDB79.4000100@hardwarefreak.com> (raw)
In-Reply-To: <4D3CB72E.3050000@harddata.com>
Maurice Hilarius put forth on 1/23/2011 5:18 PM:
> On 1/23/2011 2:24 PM, Stan Hoeppner wrote:
>> ..
>>> Chenbro backplanes do not support 6Gb SAS/SATA.
>> Considering no single (mech) drive can push 600 MB/s, let alone 300 MB/s, is
>> this really an issue?
> Yes.
> I have seen it first hand.
> If you connect 6GB drives and interfaces to it, you see a lot of errors.
> One has to be careful to set all devices to 3GB, assuming the devices have
> jumpers or other means to do so.
Which chassis model was this?
>> Mech drives aren't even going to be surpassing 300 MB/s
>> in the foreseeable future.
>>
> Perhaps, but their buffers do, and if one uses expanders it is useful
The _real world_ application performance difference between SATA II and SATA III
mech drive interfaces is something on the order of 1%. With SSDs a little more
as some of them can actually push data faster than 3 Gb/s.
Upstream of an expander the additional b/w is useful, not downstream.
--
Stan
next prev parent reply other threads:[~2011-01-24 1:52 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-01-21 16:00 Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users Michael Evans
2011-01-21 19:04 ` Stan Hoeppner
2011-01-22 5:50 ` Michael Evans
2011-01-22 16:04 ` Stan Hoeppner
2011-01-22 20:36 ` Michael Evans
2011-01-22 22:42 ` Matt Garman
2011-01-22 23:40 ` Spelic
2011-01-23 2:44 ` Andre Tomt
2011-01-23 3:19 ` Michael Evans
2011-01-23 4:00 ` Spelic
2011-01-24 11:45 ` Sven Eschenberg
2011-01-23 0:49 ` Stan Hoeppner
[not found] ` <4D3C64CB.2080002@harddata.com>
[not found] ` <4D3C9C94.8090607@hardwarefreak.com>
[not found] ` <4D3CB72E.3050000@harddata.com>
2011-01-24 1:52 ` Stan Hoeppner [this message]
2011-01-24 3:28 ` John Robinson
2011-01-24 11:27 ` Mark Knecht
2011-01-24 11:56 ` John Robinson
2011-01-24 23:09 ` Leslie Rhorer
2011-01-24 22:06 ` Leslie Rhorer
2011-01-25 18:30 ` Maurice Hilarius
2011-01-25 20:00 ` Stan Hoeppner
2011-01-24 21:58 ` Leslie Rhorer
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