Re: SCSI vs SATA

On 4/5/07, jason(at)ohloh(dot)net <jason(at)ohloh(dot)net> wrote:
>
> On Apr 5, 2007, at 4:09 AM, Ron wrote:
>
> > BE VERY WARY OF USING AN ADAPTEC RAID CONTROLLER!
>
> Thanks - I received similar private emails with the same advice. I
> will change the controller to a LSI MegaRAID SAS 8408E -- any
> feedback on this one?

We use the LSI SAS1064 SAS chips and they've been great.

>
> >
> > IME, they are usually the worst of the commodity RAID controllers
> > available.
> > I've often seen SW RAID outperform them.
> >
> > If you are going to use this config, Tyan's n3600M (AKA S2932) MB
> > has a variant that comes with 8 SAS + 6 SATA II connectors.
> > The SKU is S2932WG2NR.
> > http://www.tyan.us/product_board_detail.aspx?pid=453
>
> I plan on leveraging the battery backed module so onboard sas isn't a
> priority for me.
>
> > I'm using this beast (Dual Socket F, AMD Barcelona ready, 16 DIMMS
> > supporting up to 64GB of ECC RAM, 2 PCI-Ex16 slots w/ PCI-Ex8
> > signalling, etc:
> > ~$450 US w/o SAS, ~$500 US w/ SAS) for my most recent pg 8.2.3
> > build on top of XFS.
>
> I'm curious to know why you're on xfs (i've been too chicken to stray
> from ext3).

I've had great performance with jfs, however there are some issues
with it on certain bigendian platforms.

>
> > If the on board RAID is or becomes inadequate to your needs, I'd
> > strongly suggest either 3ware or Areca RAID controllers.
>
> I don't know why, but my last attempt at using an areca 1120 w/ linux
> on amd64 (and > 4gb ram) was disastrous - i will never use them
> again. 3ware's been rock solid for us.
>
> >
> > Side Note:
> > What kind of HDs are the 8*73GB ones? If they are the new 2.5"
> > Savvio 15Ks, be =VERY= careful about having proper power and
> > cooling for them.
> > 14 HD's in one case are going to have a serious transient load on
> > system start up and (especially with those SAS HDs) can generate a
> > great deal of heat.
>
> I went w/ Fujitsu. Fortunately these servers are hosted in a very
> well ventilated area so i am not that concerned with heat issues.
>

We have the 2.5" drives (seagates and fujitsus) and they have been
reliable and performed well.

Alex