From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Martin K. Petersen" Subject: Re: RFC: detection of silent corruption via ATA long sector reads Date: Sun, 04 Jan 2009 21:45:40 -0500 Message-ID: References: <49580061.9060506@yahoo.com> <87f94c370901021226j40176872h9e5723c6da4afcbe@mail.gmail.com> <495F6622.9010103@anonymous.org.uk> <4960AC15.8030207@anonymous.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: In-Reply-To: <4960AC15.8030207@anonymous.org.uk> (John Robinson's message of "Sun\, 04 Jan 2009 12\:31\:17 +0000") Sender: linux-raid-owner@vger.kernel.org To: John Robinson Cc: "Martin K. Petersen" , linux-raid@vger.kernel.org List-Id: linux-raid.ids >>>>> "John" == John Robinson writes: John> Essentially DIF on 32k blocks instead of 512 byte ones. But John> perhaps this is a bad assumption and MD/DM already optimises out John> whole-chunk reads and writes where they're not required (for very John> short, less-than-one-chunk transactions), and I've no idea whether John> this happens a lot. I haven't looked at the RAID4/5/6 code for a long time so I'm not sure whether they only write dirty pages or the whole chunk + parity ditto. Neil? -- Martin K. Petersen Oracle Linux Engineering