On Wed, 2008-12-10 at 19:11 -0500, Bill Davidsen wrote: > Justin Piszcz wrote: > > Point of thread: Two problems, mentioned in detail below, NCQ in Linux > > when used in a RAID configuration and two, something with how Linux > > interacts with the drives causes lots of problems as when I run the WD > > tools on the disks, they do not show any errors. > > > > If anyone has/would like me to run any debugging/patches/etc on this > > system feel free to suggest/send me things to try out. After I put > > the VR's in a test system, I left NCQ enabled and I made a 10 disk > > raid5 to see how fast I could get it to fail, I ran bonnie++ shown > > below as a disk benchmark/stress test: > > > > For the next test I will repeat this one but with NCQ disabled, having > > NCQ enabled makes it fail very easily. Then I want to re-run the test > > with RAID6. > > > > bonnie++ -d /r1/test -s 1000G -m p63 -n 16:100000:16:64 > > > > $ df -h > > /dev/md3 2.5T 5.5M 2.5T 1% /r1 > > > > And the results? Two disk "failures" according to md/Linux within a > > few hours as shown below: > > > > Note, the NCQ-related errors are what I talk about all of the time, if > > you use > > NCQ and Linux in a RAID environment with WD drives, well-- good luck. > > > > Two-disks failed out of the RAID5 and I currentlty cannot even 'see' > > one of the drives with smartctl, will reboot the host and check sde > > again. > > > > After a reboot, it comes up and has no errors, really makes one wonder > > where/what the bugs is/are, there are two I can see: > > 1. NCQ issue on at least WD drives in Linux in SW md/RAID > > 2. Velociraptor/other disks reporting all kinds of sector errors etc, > > but when you use the WD 11.x disk tools program and run all of their > > tests it says the disks have no problems whatsoever! The smart > > statistics do confirm this. Currently, TLER is on for all disks, for > > the duration of these tests. > > Just a few comments on this, I have several RAID arrays built on Seagate > using NCQ, and yet to have a problem. I have NCQ on with my WD drives, > non-RAID, and haven't had an issue with them either. The WDs run a lot > cooler than the SG, but they are probably getting less use, as well. If > the WD are still on sale after the holiday I may grab a few more and run > RAID, by then I will have some small sense of trusting them. Velociraptors, or which WD? > -- 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
