At 11:02 AM 12/7/2006, Gene wrote:
I'm building a SuperServer 6035B server (16 scsi drives). My schema
has basically two large tables (million+ per day) each which are
partitioned daily, and queried independently of each other. Would
you recommend a raid1 system partition and 14 drives in a raid 10 or
should i create separate partitions/tablespaces for the two large
tables and indexes?
Not an easy question to answer w/o knowing more about your actual
queries and workload.
To keep the math simple, let's assume each SCSI HD has and ASTR of
75MBps. A 14 HD RAID 10 therefore has an ASTR of 7* 75= 525MBps. If
the rest of your system can handle this much or more bandwidth, then
this is most probably the best config.
Dedicating spindles to specific tables is usually best done when
there is HD bandwidth that can't be utilized if the HDs are in a
larger set +and+ there is a significant hot spot that can use
dedicated resources.
My first attempt would be to use other internal HDs for a RAID 1
systems volume and use all 16 of your HBA HDs for a 16 HD RAID 10 array.
Then I'd bench the config to see if it had acceptable performance.
If yes, stop. Else start considering the more complicated alternatives.
Remember that adding HDs and RAM is far cheaper than even a few hours
of skilled technical labor.
Ron Peacetree
