On Fri, Apr 11, 2014 at 05:41:12PM +0530, Manibalan P wrote: > Hi Neil, > > Also, I found the data corruption issue on RHEL 6.5. > Did you file a bug about the corruption to redhat bugzilla? -- Pasi > For your kind attention, I up-ported the md code [raid5.c + raid5.h] > from FC11 kernel to CentOS 6.4, and there is no mis-compare with the > up-ported code. > > Thanks, > Manibalan. > > -----Original Message----- > From: Manibalan P > Sent: Monday, March 24, 2014 6:46 PM > To: 'linux-raid@xxxxxxxxxxxxxxx' > Cc: neilb@xxxxxxx > Subject: RE: raid6 - data integrity issue - data mis-compare on > rebuilding RAID 6 - with 100 Mb resync speed. > > Hi, > > I have performed the following tests to narrow down the integrity issue. > > 1. RAID 6, single drive failure - NO ISSUE > a. Running IO > b. mdadm set faulty and remove a drive > c. mdadm add the drive back > There is no mis-compare happen in this path. > > 2. RAID 6, two drive failure - write during Degrade and verify after > rebuild > a. remove two drives, to make the RAID array degraded. > b. now run write IO write cycle, wait till the write cycle > completes > c. insert the drives back one by one, and wait till the re-build > completes and a RAID array become optimal. > d. now perform the verification cycle. > There is no mis-compare happened in this path also. > > During All my test, the sync_Speed_max and min is set to 100Mb > > So, as you referred in your previous mail, the corruption might be > happening only during resync and IO happens in parallel. > > Also, I tested with upstream 2.6.32 kernel from git: > "http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/ - > tags/v2.6.32" > And I am facing mis-compare issue in this kernel as well. on > RAID 6, two drive failure with high sync_speed. > > Thanks, > Manibalan. > > -----Original Message----- > From: NeilBrown [mailto:neilb@xxxxxxx] > Sent: Thursday, March 13, 2014 11:49 AM > To: Manibalan P > Cc: linux-raid@xxxxxxxxxxxxxxx > Subject: Re: raid6 - data integrity issue - data mis-compare on > rebuilding RAID 6 - with 100 Mb resync speed. > > On Wed, 12 Mar 2014 13:09:28 +0530 "Manibalan P" > <pmanibalan@xxxxxxxxxxxxxx> > wrote: > > > > > > >Was the array fully synced before you started the test? > > > > Yes , IO is started, only after the re-sync is completed. > > And to add more info, > > I am facing this mis-compare only with high resync speed > > (30M to 100M), I ran the same test with resync speed min -10M and max > > - 30M, without any issue. So the issue has relationship with > > sync_speed_max / min. > > So presumably it is an interaction between recovery and IO. Maybe if we > write to a stripe that is being recoverred, or recover a stripe that is > being written to, then something gets confused. > > I'll have a look to see what I can find. > > Thanks, > NeilBrown > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
