From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Martin K. Petersen" Subject: Re: RAID-10 keeps aborting Date: Wed, 5 Jun 2013 12:29:32 -0700 (PDT) Message-ID: References: <51AC1440.7020505@zytor.com> <51AC3283.4000403@zytor.com> <51ACBAA0.40604@zytor.com> <51ACD511.4030604@zytor.com> <51AE2A8C.4080508@zytor.com> <51AE3441.3000208@zytor.com> <51AEA4FE.3060900@zytor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ascii Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <51AEA4FE.3060900@zytor.com> <(H.> <"Tue> <> <04> <2013> <19:39:58> <-0700")> Sender: linux-raid-owner@vger.kernel.org To: "H. Peter Anvin" Cc: Dan Williams , "Martin K. Petersen" , linux-raid , joe.lawrence@stratus.com List-Id: linux-raid.ids >>>>> "hpa" == H Peter Anvin writes: hpa> Yuck, this suddenly got complex. Perhaps WRITE SAME should simply hpa> be disabled on raid1/raid10 until this can be addressed? Yeah, maybe. hpa> Do we need to do the same for DISCARD? For discard we have better heuristics from the device so the partial completion case should be rare. But obviously a disk can reject a command anytime with or without reason... Also, discard is advisory. There is no guarantee that a pair of mirrored drives will be consistent in the discarded region (unless the drives promise to zero discarded blocks but MD doesn't check that for raid1/raid10). WRITE SAME requires strict consistency between the devices, however. So it looks like there's some work that needs to be done in that department. -- Martin K. Petersen Oracle Linux Engineering