Re: SCSI disk: still the way to go?

Compare these two drives:

http://www.storagereview.com/php/benchmark/suite_v4.php?typeID=10&testbedID=4&osID=6&raidconfigID=1&numDrives=1&devID_0=279&devID_1=308&devCnt=2

Prices:

http://www.cdw.com/shop/products/default.aspx?EDC=984588 - SAS - ~$950
http://www.cdw.com/shop/products/default.aspx?EDC=912784 SATA - ~$320

For a third of the price you can have 90% of the throughput performance, which is probably where you will be most stressing your drives in a data warehouse.

I have only seen good benchmarks from LSI's MegaRAID controllers for SCSI in linux, I have seen good results from LSI, 3Ware (now AMCC) and Areca in Linux for their SATA products (in RAID 10).  There are plenty of large drive number chasis out there with SATA hot swap bays if you want them.  Tyan makes a great dual CPU board with two independant PCI-X buses. that will give 1066MB/sec total through put each which I have great benchmark number from.

it's possible to reach these numbers with SAN, but it will cost major major $$s.  Each FC line in a SAN is typically 2Gb last time I checked, so you need multiple channels to acheive a max of 1066MB/sec throughput per PCI-X bus.  If you run the numbers, you theoretically need 24 drives in a RAID 10 to get max throughput (Areca makes a 24 channel SATA card: http://www.newegg.com/Product/Product.asp?Item=N82E16816151004 - Although I couldn't find one with multilane support).  I have seen chassis that can hold 40 drives.  If you go for the 74Gig cousin that has similar throughput, which you can get OEM for $160/each you are talking just about $6400 in drives, plus about $4k for the chasis ( http://rackmountmart.stores.yahoo.net/rm8uracchasw.html), plus about $5k for other components (depending on RAM/CPU), so a massively kick ass whitebox can be had for about $16k that will acheive close to the maximum theoretical throughput acheivable in a single server for MB/sec.

Now there are arguments to be had about splitting up table spaces etc, but I present this as a concrete example of components that can be had for not alot of money to build a majorly kick ass server using SATA technology.

Alex