Re: Bad iostat numbers

On Mon, 2006-12-04 at 11:43, Michael Stone wrote:
> On Mon, Dec 04, 2006 at 12:37:29PM -0500, Alex Turner wrote:
> >This discussion I think is important, as I think it would be useful for this
> >list to have a list of RAID cards that _do_ work well under Linux/BSD for
> >people as recommended hardware for Postgresql. So far, all I can recommend
> >is what I've found to be good, which is 3ware 9500 series cards with 10k
> >SATA drives. Throughput was great until you reached higher levels of RAID
> >10 (the bonnie++ mark I posted showed write speed is a bit slow). But that
> >doesn't solve the problem for SCSI. What cards in the SCSI arena solve the
> >problem optimally? Why should we settle for sub-optimal performance in SCSI
> >when there are a number of almost optimally performing cards in the SATA
> >world (Areca, 3Ware/AMCC, LSI).
>
> Well, one factor is to be more precise about what you're looking for; a
> HBA != RAID controller, and you may be comparing apples and oranges. (If
> you have an external array with an onboard controller you probably want
> a simple HBA rather than a RAID controller.)

I think he's been pretty clear. He's just talking about SCSI based RAID
controllers is all.