Laszlo Nagy wrote:
> Hello,
>
> I'm about to buy SSD drive(s) for a database. For decision making, I
> used this tech report:
>
> http://techreport.com/articles.x/16255/9
> http://techreport.com/articles.x/16255/10
>
> Here are my concerns:
>
> * I need at least 32GB disk space. So DRAM based SSD is not a real
> option. I would have to buy 8x4GB memory, costs a fortune. And
> then it would still not have redundancy.
> * I could buy two X25-E drives and have 32GB disk space, and some
> redundancy. This would cost about $1600, not counting the RAID
> controller. It is on the edge.
> * I could also buy many cheaper MLC SSD drives. They cost about
> $140. So even with 10 drives, I'm at $1400. I could put them in
> RAID6, have much more disk space (256GB), high redundancy and
> POSSIBLY good read/write speed. Of course then I need to buy a
> good RAID controller.
>
> My question is about the last option. Are there any good RAID cards
> that are optimized (or can be optimized) for SSD drives? Do any of you
> have experience in using many cheaper SSD drives? Is it a bad idea?
>
> Thank you,
>
> Laszlo
>
Note that some RAID controllers (3Ware in particular) refuse to
recognize the MLC drives, in particular, they act as if the OCZ Vertex
series do not exist when connected.
I don't know what they're looking for (perhaps some indication that
actual rotation is happening?) but this is a potential problem.... make
sure your adapter can talk to these things!
BTW I have done some benchmarking with Postgresql against these drives
and they are SMOKING fast.
-- Karl