He's talking about RAID 1 here, not a gargantuan RAID 6. Onboard RAM
on the controller card is going to make very little difference. All
it will do is allow the card to re-order writes to a point (not all
cards even do this).
Alex.
On 1/18/06, William Yu <wyu@talisys.com> wrote:
> Benjamin Arai wrote:
> > Obviously, I have done this to improve write performance for the update
> > each week. My question is if I install a 3ware or similar card to
> > replace my current software RAID 1 configuration, am I going to see a
> > very large improvement? If so, what would be a ball park figure?
>
> The key is getting a card with the ability to upgrade the onboard ram.
>
> Our previous setup was a LSI MegaRAID 320-1 (128MB), 4xRAID10,
> fsync=off. Replaced it with a ARC-1170 (1GB) w/ 24x7200RPM SATA2 drives
> (split into 3 8-drive RAID6 arrays) and performance for us is through
> the ceiling.
>
> For OLTP type updates, we've gotten about +80% increase. For massive
> 1-statement updates, performance increase is in the +triple digits.
>
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