Re: Hardware/OS recommendations for large databases

Got some hard numbers to back your statement up?  IME, the Areca 
1160's with  >= 1GB of cache beat any other commodity RAID 
controller.  This seems to be in agreement with at least one 
independent testing source:

http://print.tweakers.net/?reviews/557

RAID HW from Xyratex, Engino, or Dot Hill will _destroy_ any 
commodity HW solution, but their price point is considerably higher.

...on another note, I completely agree with the poster who says we 
need more cache on RAID controllers.  We should all be beating on the 
RAID HW manufacturers to use standard DIMMs for their caches and to 
provide 2 standard DIMM slots in their full height cards (allowing 
for up to 8GB of cache using 2 4GB DIMMs as of this writing).

It should also be noted that 64 drive chassis' are going to become 
possible once 2.5" 10Krpm SATA II and FC HDs become the standard next 
year (48's are the TOTL now).  We need controller technology to keep up.

Ron

At 12:16 AM 11/16/2005, Alex Turner wrote:
>Not at random access in RAID 10 they aren't, and anyone with their
>head screwed on right is using RAID 10.  The 9500S will still beat the
>Areca cards at RAID 10 database access patern.
>
>Alex.
>
>On 11/15/05, Dave Cramer  wrote:
> > Luke,
> >
> > Have you tried the areca cards, they are slightly faster yet.
> >
> > Dave
> >
> > On 15-Nov-05, at 7:09 AM, Luke Lonergan wrote:
> >
> >
> >
> >
> >
> > I agree - you can get a very good one from www.acmemicro.com or
> >
> > www.rackable.com with 8x 400GB SATA disks and the new 3Ware 9550SX SATA
> >
> > RAID controller for about $6K with two Opteron 272 CPUs and 8GB of RAM
> >
> > on a Tyan 2882 motherboard.  We get about 400MB/s sustained disk read
> >
> > performance on these (with tuning) on Linux using the xfs filesystem,
> >
> > which is one of the most critical factors for large databases.
> >
> >
> >
> >
> > Note that you want to have your DBMS use all of the CPU and disk channel
> >
> > bandwidth you have on each query, which takes a parallel database like
> >
> > Bizgres MPP to achieve.
> >
> >
> >
> >
> > Regards,
> >
>
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