> -----Original Message----- > From: linux-raid-owner@xxxxxxxxxxxxxxx [mailto:linux-raid- > owner@xxxxxxxxxxxxxxx] On Behalf Of Lelsie Rhorer > Sent: Sunday, April 05, 2009 12:21 AM > To: linux-raid@xxxxxxxxxxxxxxx > Subject: RE: > > > You should note that the drive won't know a sector it just wrote is > > bad until it reads it > > Yes, but it also won't halt the write for 40 seconds because it was > bad. > More to the point, there is no difference at the drive level between a > bad > sector written for a 30Gb file and a 30 byte file. > > > ....are you sure you actually successfully wrote all of that data and > that > >it is still there? Pretty sure, yeah. There are no errors in the > filesystem, and every file I have written works. Again, however, the > point > is there is never a problem once the file is created, no matter how > long it > takes to write it out to disk. The moment the file is created, > however, > there may be up to a 2 minute delay in writing its data to the drive. > > > And it is not the writes that kill when you have a drive going bad, > it > > is the reads of the bad sectors. And to create a file, a number of > > things will likely need to be read to finish the file creation, and > if > > one of those is a bad sector things get ugly. > > Well, I agree to some extent, except that why would it be loosely > related to > the volume of drive activity, and why is it 5 drives stop reading > altogether > and 5 do not? Furthermore, every single video file gets read, re- > written, > edited, re-written again, and finally read again at least once, > sometimes > several times, before being finally archived. Why does the kernel log > never > report any errors of any sort? > > -- > 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 All of what you report is still consistent with delays caused by having to remap bad blocks The O/S will not report recovered errors, as this gets done internally by the disk drive, and the O/S never learns about it. (Queue depth settings can account for some of the other "weirdness" you reported. Really, if this was my system I would run non-destructive read tests on all blocks; along with the embedded self-test on the disk. It is often a lot easier and more productive to eliminate what ISN'T the problem rather than chase all of the potential reasons for the problem. -- 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
