Raid 10 vs 15K SAS

[steven08]

I am going to upgrade my Transaction Processing Server (still running Window 2000 Server OS). It has extensive Read/Write operations from time to time. R/W performance (especially the write) is my top priority while reliability is the second priority (as I will still carry out scheduled backup daily). I do not know which would be the best configuration :

Raid 10 using 4 SATA II 3.0Gb/sec HD (Intel Server board has onboard Raid 0, 1, 5, & 10) OR
a single 15K SAS HD

Please kindly give me some advise

Thanks a lot.

 

[GhislainG]

You could read http://blogs.zdnet.com/Ou/?p=484&page=1, but bear in mind that the single drive he used is not a 15K SAS unit. Depending on the SATA drives that you'll use, a 15K SAS drive might be quicker, but not as safe. You could also check the "IOMeter File Server 1 I/O" benchmarks at http://www.storagereview.com/php/benchmark/bench_sort.php.

 

[br3nd064]

If you're not concerned with reliability, I think 4 drives in raid 0 would be the fastest for overall bandwidth. If you're doing a lot of small read/writes, though, the 15k drive would be better.

 

[cjl]

For lots of I/O, you want the 15k. For fast sequentials, you want the RAID.

 

[steven08]

Thanks for all the useful advises. I studied the benchmarks charts in Tom's Hardware. The IO Meter File Server benchmark of a single SAS drive (Seagate Cheetah 15K.5) is way out perform any RAID configuration:

Cheetach 15K.5 SAS HDD == 2075.03
RAID 0 (4 drives) == 960.18
RAID 10 (4 drives) == 812.23

For the sequential read and write, the RAID is better though:

Cheetach 15K.5 SAS HDD == 107.80 (Ave Read Transfer) / 104.70 (Ave Write Transfer)
RAID 0 (4 drives) == 302.20 (Ave Read Transfer) / 273.30 (Ave Write Transfer)
RAID 10 (4 drives) == 153.60 (Ave Read Transfer) / 154.80 (Ave Write Transfer)

However, for a more meaningful comparison, I want to know what kind of hard drives are being used in these RAID configuration for these benchmark tests. I looked around but there was no description for the hardware configuaration under the RAID Matrix Charts. Does anyone has the answers?

Thanks again.

 

[GhislainG]

Click the Test Platform icon for details. They used "Samsung HD120IJ (120 GB 7,200 RPM, 8 MB Cache, SATA/300)" which are not as afast as newer SATA drives.

 

[cjl]

True, but even the latest SATA won't come close to matching a Cheetah for IO.