From mboxrd@z Thu Jan 1 00:00:00 1970 From: "spren.gm@gmail.com" Subject: Re: Re: why md/raid5 dont have bad block remap Date: Mon, 28 Dec 2009 19:49:04 +0800 Message-ID: <200912281948566259320@gmail.com> References: , , , Return-path: Sender: linux-raid-owner@vger.kernel.org To: Mikael Abrahamsson , jin zhencheng Cc: "linux-raid@vger.kernel.org" List-Id: linux-raid.ids > from:Mikael Abrahamsson >On Mon, 28 Dec 2009, jin zhencheng wrote: > >> I think maybe the disk deal with one write comnd with errror,but the >> disk maybe is also ok,and rewrite to other place or rewrite again >> will be good. >> >> why one write error ,set the whole disk faulty. > >If the disk has *WRITE* errors, something is seriously wrong. Read errors >is one thing, write errors is completely different. > >> Disk if very expensive! > >Most drives have at least 2-3 years warranty and that should be used. If >the drive has write errors, then it's really time to replace it, it won't >be reliable. I agree, the capacity and safety of data is the most important issue for raid layer, if a write error happens on one drive, more errors may soonly follow, where and how much will be remapped? it would involve complicated algorithms and may cause serious performance decline. ------------------ spren.gm@gmail.com 2009-12-28