From mboxrd@z Thu Jan 1 00:00:00 1970 From: Randy Terbush Subject: Re: Possibility for a parallel relaxed RAID? Date: Thu, 18 Mar 2010 17:00:04 -0600 Message-ID: <7db987b31003181600v30e7efeboaf7c8d0d40dde429@mail.gmail.com> References: <4BA27898.4010907@panix.com> <20100319085414.6cdddd29@notabene.brown> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20100319085414.6cdddd29@notabene.brown> Sender: linux-raid-owner@vger.kernel.org To: Neil Brown Cc: Berkey B Walker , linux raid List-Id: linux-raid.ids Neil, How does md make the decision to drop a drive from the array? Is it a fail message back from the ATA layer? Quickly getting over my head here, but I would like to think there are different types of failures and a failure to complete error correction on the drive should not be a fatal error to md. This request is the same as the post I have made earlier this week regarding "RAID class" drives which I would love to get your response to. Tks On Thu, Mar 18, 2010 at 3:54 PM, Neil Brown wrote: > On Thu, 18 Mar 2010 15:01:44 -0400 > Berkey B Walker wrote: > >> There maybe many folks out there who want to use RAID on their perso= nal, >> non-production systems. =A0Assuming access and thru-put values are n= ot >> critical a problem might be "You can't use Desktop drives for RAID". >> Which, I think, most of us know is not really true, but - - If the >> timing issues were to be relaxed, allowing the drive to fix itself, >> before being kicked by the md process, might not the average Joe be >> better served? =A0There is a big difference between going a mile and >> buying a commodity drive, and being "up" in an hour vs. finding a >> working system, going online, paying price+, and getting/paying fast >> shipping. Which might resolve the issue in days instead of hours. >> >> Any possibility of a parallel, less critical to drive response, rele= ase >> of md? =A0Or a patch to allow same? > > This is not a function of 'md'. =A0md has no timeouts for drives resp= onding. > It just submits a request and waits for a success/fail reply. > > It may be a function of the lower level SATA/SCSI/FC/whatever driver.= =A0You > would do better to ask the developers of those drivers, maybe start w= ith the > maintainer of libata. > > NeilBrown > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid"= in > the body of a message to majordomo@vger.kernel.org > More majordomo info at =A0http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-raid" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html