Dual for me. I'd also go for the SATA in RAID 1.

10K scsi IMO, you want your database server processors processing sql queries, not lookups to the hardrives.

"a VERY BUSY DATABASE SERVER" => SCSI in RAID10 (better than RAID1, though requires 4 disks), RAID5 would probably be worse as it's slower for many small random writes, which is a typical db workload.

10k SCSI or especially (SAS) Serial Attached SCSI without a second thought

Not exactly fair unless you are talking just raw speed. I look at RAID more for redundancy but as you add drives you will pick up performance boosts, especially in reads. I would still opt for 10k SCSI
Your tempting me now since you have 4 drives.. How good is your RAID card? :p
If you now take the 10k SCSI drives and add a good RAID card you will likely have a great database server.. Very fast if running RAID 10 or even a lot of drives in RAID 5 and full redundancy.

Doc, with all due respect you are asking for trade-offs (IMO) on each this vs. that setup. I mean, if you asked me if I would go with the 10 SCSI (no Raid) with ether a Xeon or Opterson vs. a 10k Raptor SATA RAID 0 setup utilizing a Xeon or Opteron processor it would be easier to decide on but when I look at this my opinion is you handicap your setups. It's like good processor with ok drive setup or ok processor with a good drive setup.

I am no hardware guru but before I just dropped $6,470.00 on a server I studied this stuff pretty hard. I went back and forth with multiple server setups to single power-houses.. I looked at SATA Raptor 10k drives, SATA RAID controllers, SCSI u320 10k & 15k drives and finally learned about SAS 10k & 15k Cheetah, Atlas and other drives.

In the final analysis and my conclusion after reading for literally days on the subject is this: In a database server environment SCSI simply beats all SATA drives on the market today, including the Raptors (which I dearly love for my home PC and would use in a web server), especially when you get into RAID configurations..

And speaking of RAID setups... I studied this and asked everyone under the sun on which is the best... And for a screaming fast database server, the consensus seems to be RAID 10.

Your forums are undeniably large any way you look at them.. Personally, I would not even consider a SATA setup for your databases. You need a good RAID 10 or maybe a 5 setup with a lot of drives for your database server, IMO.

Here are the specifications of the server that I just purchased. It was designed to handle both our web & database needs for the emmediate future. When we need more I will add web sever(s) and transition this server to handle only database usage. When that time comes I will feel comfortable having single or dual opteron 1u server(s) that run a RAID-1 using (2) Raptor drives. Until then, I think it will be plenty.

One thing of note with regards to my server and pricing. It would have been a good deal cheaper if I had not gone with the SAS drives and the RAID card spec'd. I had a really nice RAID 10 setup with (4) 15k Cheetah drives for a little bit over $4,000.00 and would have been an awesome database server. I had plans to use that and also a web server but decided it would be more practical to just build a "monster" to handle our needs for now and save me hosting expenses at this point in time.

Spec's:
2x AMD Opteron 270 Dual-Core socket 940 CPUs (4 cores total)
Supermicro H8DAE dual socket 940 server board
8G DDR-400 PC-3200 ECC Registered, NUMA
Adaptec 4800SAS 8-port hardware SAS RAID controller, 133mhz PCI-X
2x Maxtor Atlas 73-Gig SAS, 15k rpm (RAID-1 for OS)
4x Maxtor Atlas 36-Gig SAS, 15k rpm (RAID-10 for data)
1x Seagate Barracuda 300-Gig IDE, 7200rpm (for backup)
on-board broadcom dual gigabit NICs
Supermicro IPMI 2.0 adapter (AOC-1UIPMI-B)
on-board ATI rage Video, 8M
24x slim CD-ROM; 1.44M Floppy
SuperMicro SC822T-R500RC 2U Rack-mount Chassis
6x Hot-swap HDD Carriers & 1x6 SATA/SAS Backplane
dual SuperMicro 500watt Redundant Power Supplies

Thanks for all the responses and help. :)

I currently run SCSI on all my servers, just being tempted to a different DC with better CPUs but Raptors. Looks like I will need to keep my SCSIs...

Erwin, once you go SCSI, you don't go back. ;)

lol... :banana:

You know, if you could offer me a quad opteron system with like 20 Raptor 10k drives and some really awesome RAID card(s), I might do that.. ;)

The only down-side to SCSI as we all know are the prices for the drives. I think the SAS hard drives for my new server cost more than the dang server. For web hosting companies, it is a lot cheaper to offer the SATA drives and an opteron box than messing with SCSI. I tried and tried to get a few different dedicated server providers to put together a good deal for me using Opterons and SCSI HD's/RAID and every time we tried to work in the SCSI u320 drives and RAID card it priced it way up beyond what I wanted to pay. I'll for sure go with them (10k SATA) when I need new web servers but not for data base.

Ok, I'll shut up now ;)

What do people make of this article?
http://www.pugetsystems.com/articles.php?id=19

Also...

In terms of speed (forgetting about risk/data loss/life span etc), which one would you choose:

1) 10k Raptor NCQ x 4 in RAID 0 setup

OR

2) 10 k SCSI x 1, non-RAID

(note: both disks at 10k)

???

Are all 4 drives part of this RAID 0 array?
I would guess that would create maxium throughput but if one fails, but data loss is a big risk on this setup due to a failure. So maximum on both accounts. ;)