Trouble with SSD on SATA
freebsd at jdc.parodius.com
Thu Nov 17 11:20:16 UTC 2011
On Thu, Nov 17, 2011 at 12:03:26PM +0100, Willem Jan Withagen wrote:
> On 2011-11-16 18:22, Peter Maloney wrote:
> >I can only guess, but...
> >Is AHCI enabled in the bios? If you are not using 'fake-raid' for any
> >disks, you should [depending on FreeBSD version, HBA, etc.] probably
> >enable AHCI. Some servers actually come with SATA set in IDE mode. And
> >if you are using zfs, the controller optimally should not be RAID at
> >all. And if you have AHCI enabled already, try disabling it (losing hot
> >swapping ability, and some performance).
> ACHI is enabled otherwise I cannot used the last set of SATA
> connectors with this MB. Controller for these connectors is CH9.
There are two "kinds" of AHCI on FreeBSD -- and I'm speaking strictly
about the kernel bits, not AHCI the option ROM/BIOS option:
ataahci.ko -- this is "AHCI support using ata(4)"
ahci.ko -- this is "AHCI support using CAM(4)"
You want the latter, and I can tell you're using the former (if at all).
There would be no "ata6" if you were using ahci.ko; it would be called
something like ahcichX, indicating "AHCI channel X". Furthermore,
because CAM(4) gets used, your disk device names change from adX to
adaX. This is expected. Using ataahci.ko results in the disks still
being named adX, because it uses ata(4).
Hope this helps shed some light on the confusion. Generally speaking
you want to be using ahci.ko, mav@ and many others have spent a lot of
time working on that and getting it to play nice with CAM -- it's
beautiful, and hot-swapping works perfectly on all the Intel ICHxx
systems I've tried it on (ICH7R, ICH9R).
| Jeremy Chadwick jdc at parodius.com |
| Parodius Networking http://www.parodius.com/ |
| UNIX Systems Administrator Mountain View, CA, US |
| Making life hard for others since 1977. PGP 4BD6C0CB |
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