hardware for home use large storage

[Dan Langille]

On Tue, February 9, 2010 10:16 am, Tom Evans wrote:
> On Tue, Feb 9, 2010 at 3:01 PM, Dan Langille <dan at langille.org> wrote:
>>
>> On Tue, February 9, 2010 9:09 am, Tom Evans wrote:
>>> On Tue, Feb 9, 2010 at 1:45 PM, Dan Langille <dan at langille.org> wrote:
>>> One thing to point out about using a PM like this: you won't get
>>> fantastic bandwidth out of it. For my needs (home storage server),
>>> this really doesn't matter, I just want oodles of online storage, with
>>> redundancy and reliability.
>>
>>
>> A PM? Â What's that?
>>
>> Yes, my priority is reliable storage. Â Speed is secondary.
>>
>> What bandwidth are you getting?
>>
>
> PM = Port Multiplier
>
> I'm getting disk speed, as I only have one device behind the PM
> currently (just making sure it works properly :). The limits are that
> the link from siis to the PM is SATA (3Gb/s, 375MB/s), and the siis
> sits on a PCIe 1x bus (2Gb/s, 250 MB/s), so the bandwidth from that is
> shared amongst the up-to 5 disks behind the PM.
>
> Writing from /dev/zero to the pool, I get around 120MB/s. Reading from
> the pool, and writing to /dev/null, I get around 170 MB/s.
>

That leads me to conclude that a number of SATA cards is better than a
port multiplier.  But the impression I'm getting is that few of these work
well with FreeBSD.  Which is odd... I thought these cards would merely
present the HDD to the hardware and no diver was required.  As opposed to
RAID cards for which OS-specific drivers are required.


-- 
Dan Langille -- http://langille.org/