Re: [Slightly OT] Cheap 4-port PCI-E SATA card?

[John Robinson <john.robinson@anonymous.org.uk>]

On 03/01/2011 06:41, Stan Hoeppner wrote:
[...]
> Go with one or two of these SATA II port multipliers with 1 host
> interface and 5 drive interfaces--perfect for a 10 drive setup with two
> 5 drive cages.
>
> http://www.addonics.com/products/host_controller/ad5sapm.asp
>
> http://www.buy.com/prod/addonics-ad5sapm-serial-ata-controller-5-x-7-pin-serial-ata-300-serial/q/loc/101/213272437.html
>
> http://www.siliconimage.com/products/product.aspx?pid=32
>
> If your mobo SATA ports support FIS based switching, this PMP will give
> you 5 SATA II drive ports.  It doesn't use a PCI slot of any kind.  No
> additional software required.  No kernel driver issues.  300MB/s is
> sufficient for 5 drives in an mdraid setup isn't it?

For a backup array, yes, but I'm not sure it is for online storage. 
300MB/s is an absolute max and there's protocol overhead etc, but even 
if it's minimal we're still looking at no better than 50MB/s per drive, 
while the drives can manage 125MB/s these days.

I doubt my motherboard supports FIS PMPs. It's an Asus P5Q Pro, Intel 
P45+ICH10R, and I'm pretty sure the ICH10R doesn't support PMPs even if 
the original spec said it would.

There is a Marvell 88SE6121 SATA+IDE chip on there but it's currently in 
IDE-only mode for the DVD drive and even if I switched over to SATA mode 
and a SATA DVD drive that'd only give me one more SATA port. But it 
might work with a FIS PMP, I suppose.

> When I use these I remove the slot bracket and mount the PCB directly to
> my server chassis side wall using mobo type standoffs.  You may need to
> drill a couple of holes in the chassis depending on where you decide to
> mount it.  If you're not a mechanically inclined DIY type person, just
> use the supplied mounting bracket.  This may deny access to an
> underlying PCI slot though.  I prefer the more solid mount and having
> all slots available.

I'd do that too - no problems doing case mods here. I suppose it's 
possible the mounting holes might be able to be made to line up with 
some of the mounting holes on the side of the hot-swap chassis. On the 
other hand I might cheat and use the little plastic mounts with 
double-sided tape on their feet.

[...]
>   The driver for the Marvell chip is present in kernel
> 2.6.19 and later.  Considering that 2.6.19 is like 6 years old, I'd hope
> your kernel is newer.

It's kernel-2.6.18-194.26.1.el5 so it's stuffed full of backports and 
security updates, it's less than two months old. Yes, I have sata_mv, 
but several people have reported data corruption issues with some 
Marvell controllers - a bad interaction with SMART I think.

> It may be a little more money than you were planning on spending, but
> for little more than the cost of one hard drive

In this case I'm using consumer-level drives so they're about £40 ($60), 
so $165 is a bit rich for me, especially since it's potentially limited 
for throughput.

Nevertheless, thank you very much for taking the time for such a 
considered reply.

Cheers,

John.

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