AHCI and Highpoint Rocket 750

[Alan Somers]

On Mon, Jan 22, 2018 at 12:05 PM, FF <fusionfoto at gmail.com> wrote:

> oh nice! so it "just works" -- is there any way to verify it?
>

Not easily.  You could try putting a load on those disks, then use "gstat
-a" to watch the queue depth (the "L(q)" column).  If it's >1, that means
that geom is trying to use queued commands.  A more accurate but more
difficult method would be to use a benchmark program like benchmarks/fio to
do a random write test on a single disk.  If the throughput is higher when
fio is using a queue depth > 1, then that would indicate that queued
commands are making it all the way to the drive.

OTOH, it would probably be a better use of your time just to benchmark
whatever application you're using.  Only if that's too slow should you dig
into minutiae like this.  With 40 drives, you may have plenty of IOPs even
without NCQ.


>
> Is there any reason to use the highpoint driver when the native FreeBSD
> one seems to work?
>

Nope.


>
> thanks!!
>
> On Mon, Jan 22, 2018 at 1:26 PM, Alan Somers <asomers at freebsd.org> wrote:
>
>> On Mon, Jan 22, 2018 at 11:08 AM, FF <fusionfoto at gmail.com> wrote:
>>
>>> I have a machine with the Highpoint card and motherboard based SATA
>>> drives.
>>> The drives from the MB support AHCI and appear as ada0-8. The drives on
>>> the
>>> highpoint card whether using native FreeBSD support or the Highpoint
>>> provided driver show up as da9-39.
>>>
>>> It is my understanding that AHCI is needed to support NCQ... I'm
>>> wondering
>>> what I need to do to get AHCI enabled. This seems to happen in both
>>> FreeBSD
>>> 9 and FreeBSD 10.
>>>
>>> thanks in advance!
>>>
>>
>> AHCI has nothing to do with it.  The driver presents itself to the OS as
>> a SCSI HBA, even though the drives are SATA.  In fact, it might actually be
>> using a SCSI IC, but firmware-restricted to only connect to SATA drives.
>> In any case, the OS is going to try to use TCQ, and either the driver or
>> the firmware is going to translate those queued commands into NCQ.  You
>> don't need to change anything.
>>
>> -Alan
>>
>>
>
>
> --
> FF
>