I'm no drive expert, but it seems to me that our write performance is
excellent. I think what most are concerned about is OLTP where you
are doing heavy write _and_ heavy read performance at the same time.
Our system is mostly read during the day, but we do a full system
update everynight that is all writes, and it's very fast compared to
the smaller SCSI system we moved off of. Nearly a 6x spead
improvement, as fast as 900 rows/sec with a 48 byte record, one row
per transaction.
I don't know enough about how SATA works to really comment on it's
performance as a protocol compared with SCSI. If anyone has a usefull
link on that, it would be greatly appreciated.
More drives will give more throughput/sec, but not necesarily more
transactions/sec. For that you will need more RAM on the controler,
and defaintely a BBU to keep your data safe.
Alex Turner
netEconomist
On Apr 4, 2005 10:39 AM, Steve Poe <spoe@sfnet.cc> wrote:
>
>
> Alex Turner wrote:
>
> >To be honest, I've yet to run across a SCSI configuration that can
> >touch the 3ware SATA controllers. I have yet to see one top 80MB/sec,
> >let alone 180MB/sec read or write, which is why we moved _away_ from
> >SCSI. I've seen Compaq, Dell and LSI controllers all do pathetically
> >badly on RAID 1, RAID 5 and RAID 10.
> >
> >
> Alex,
>
> How does the 3ware controller do in heavy writes back to the database?
> It may have been Josh, but someone said that SATA does well with reads
> but not writes. Would not equal amount of SCSI drives outperform SATA?
> I don't want to start a "whose better" war, I am just trying to learn
> here. It would seem the more drives you could place in a RAID
> configuration, the performance would increase.
>
> Steve Poe
>
>