From mboxrd@z Thu Jan  1 00:00:00 1970
From: John Robinson <john.robinson@anonymous.org.uk>
Subject: Re: RFC: detection of silent corruption via ATA long sector reads
Date: Sat, 03 Jan 2009 13:20:34 +0000
Message-ID: <495F6622.9010103@anonymous.org.uk>
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To: "Martin K. Petersen" <martin.petersen@oracle.com>
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On 02/01/2009 22:04, Martin K. Petersen wrote:
[...]
> I wrote something akin to DIF in software by doing 64 512-byte blocks +
> 512 bytes of checksums.  The disadvantage there is having to do
> read-modify-write for small writes.  I tried several other approaches
> sacrificing both space and locality but performance was still anemic.

Excuse me if I'm being dense - and indeed tell me! - but RAID 4/5/6 
already suffer from having to do ready-modify-write for small writes, so 
is there any chance this could be done at relatively little additional 
expense for these?

Cheers,

John.