On Tue, Feb 14, 2012 at 06:17:19PM +0100, Harald Schmalzbauer wrote: > schrieb Jeremy Chadwick am 14.02.2012 17:50 (localtime): > > On Tue, Feb 14, 2012 at 04:55:10PM +0100, Claudius Herder wrote: > >> Hello, > >> > >> I have got a quite similar problem with AHCI on FreeBSD 8.2 and it still > >> persists on FreeBSD 9.0 release. > >> > >> Switching from ahci to ataahci resolved the problem for me too. > >> > >> I'm using gmirror for swap, system is on a zpool and the problem first > >> occurred during a zpool scrub, but it is easily reproducible with dd. > >> > >> The timeouts only occur when writing to disks, dd if=/dev/ada{0|1} > >> of=/dev/null is not an issue. > >> Sometimes I need to power off the server because after a reboot one disk > >> is still missing. > >> > >> I really would like to help in this issue, so let me know if you need > >> any more information. > > I find it interesting that, at least so far, the only people reporting > > problems of this type with the ahci.ko driver are people using Samsung > > disks. The only difference is that your models are F1s while the OPs > > are F2s. > > I saw such timeouts long ago and mav@ had a look at my postings and he > mentioned it could be a NCQ problem. > I suspected the disks firmware. > I never tracked it down further, because after replacing the Samsung (F3 > in that case) disks with hitachi ones solved all my problems and gave a > big performance kick as well (with zfs). > You can find the discussion here: > http://lists.freebsd.org/pipermail/freebsd-stable/2010-February/055374.html >
You gave me a good idea: try to disable NCQ and see if that's the fault. So i went and applied the attached patch. After it, i can no longer reproduce the issue with ahci driver. I know this is not a solution because it disables NCQ at controller level instead of disk level, but at least we know for sure where the problem is. I think the solution would be to add a new quirk ADA_Q_NONCQ in sys/cam/ata/ata_da.c. Quirks infraestructure is already built, so adding a new quirk for this seems easy. Is someone interested? Do you think there is a better solution? If someone is interested i can build a patch to add ADA_Q_NONCQ quirk and add my drives to it. Regards. -- La prueba más fehaciente de que existe vida inteligente en otros planetas, es que no han intentado contactar con nosotros. _______________________________________________ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"