How to best use 32 15k.7 300GB drives?

HI,

I use PostgreSQL basically as a data warehouse to store all the genetic
data that our lab generates.  The only person that accesses the database
is myself and therefore I've had it housed on my workstation in my
office up till now.  However, it's getting time to move it to bigger
hardware.  I currently have a server that is basically only storing
backup images of all our other workstations so I'm going to move my
database onto it.  The server looks like this: Windows Server Enterprise
2008 R2 64-bit, AMD 2350 quad-core x2, 32GB RAM.  For my purposes the
CPUs and RAM are fine.  I currently have an Adaptec 52445+BBU controller
that has the OS (4 drive RAID5), FTP (4 drive RAID5) and two backup
arrays (8 drive each RAID0).  The backup arrays are in a 16 drive
external enclosure through an expander so I actually have 16 ports free
on the 52445 card.  I plan to remove 3 of the drives from my backup
arrays to make room for 3 - 73GB 15k.5 drives (re-purposed from my
workstation).  Two 16 drive enclosures with SAS2 expanders just arrived
as well as 36 Seagate 15k.7 300GB drives (ST3300657SS).  I also intend
on getting an Adaptec 6445 controller with the flash module when it
becomes available in about a month or two.  I already have several
Adaptec cards so I'd prefer to stick with them.

Here's the way I was planning using the new hardware:
xlog & wal: 3 - 73G 15k.5 RAID1+hot spare in enclosure A on 52445
controller
data: 22 - 300G 15k.7 RAID10 enclosure B&C on 6445 controller
indexes: 8 - 300G 15k.7 RAID10 enclosure C on 6445 controller
2 - 300G 15k.7 as hot spares enclosure C
4 spare 15k.7 for on the shelf

With this configuration I figure I'll have ~3TB for my main data tables
and 1TB for indexes.  Right now my database is 500GB total.  The 3:1
split reflects my current table structure and what I foresee coming down
the road in terms of new data.

So my questions are 1) am I'm crazy for doing this, 2) would you change
anything and 3) is it acceptable to put the xlog & wal (and perhaps tmp
filespace) on a different controller than everything else?  Please keep
in mind I'm a geneticist who happens to know a little bit about
bioinformatics and not the reverse. :-)

Thanks!
Bob

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Robert Schnabel
Research Assistant Professor
University of Missouri-Columbia
Animal Sciences Unit, Rm.162
920 East Campus Drive
Columbia, MO 65211-5300
Phone: 573-884-4106
Fax:   573-882-6827
http://animalgenomics.missouri.edu

"...Socialist governments traditionally do make
a financial mess.  They always run out of other
people's money."

Margaret Thatcher, 5 February 1976
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