Disk IO Speed DL120G5

[Dick Richard]

We have an HP Proliant DL120G5 server with two new Seagate Barracuda 700.11 250 GB drives mirrored. Before that, we had two older Western Digital Cavalier SE 250 GB drives in the server. It has Windows 2003 Server and runs SQL 2008. HP Diagnostics show two raid controllers-- Intel ICH8 SATA Raid Controller and Intel 82801GR SATA controller.

We are running a document imaging application (DocStar) that slows to a crawl when writing to disk. Our previous server ran Docstar under Windows 2000 and MS SQL 6.5 quite satisfactorily.

When the program is writing to disk, we are getting a Disk queue length above 15 for several minutes and Avg Disk sec/Write is in the vicinity of .200. Available bytes stays pretty steady and the processor queue length is negligible.

We experience the same type of results if we copy a large file on the drives.

Sounds to me like we need faster disk IO. Any suggestions on how we can speed this system up?

[YDB]

Is there an intential decimal point in front of the 200, like in 'point 200' IOPs? If that's just an error and it's 200 IOPs, that's about all you can expect from a singe disk, since you're in a RAID 1 mirror, and 200 IOPs would be wonderful to achieve with 7.2K SATA, as that's more in the SCSI/SAS/FC IOP range.

To go faster you need things like more disk, faster disk (15K SAS), a good caching controller. There's a software product that could help in the caching that you'd put right on the server, UpTempo, from DataCore Software.