Subject: RAID and Seagate Barracuda ES.2 ST31000340NS: slow writes

While copying large amouts of data (>2 Gb) the write-rate drops down to almost zero.
After several minutes write continues.

Other disks don't suffer from this slowdown.


Product: Intel(R) Server Board S5000PSLROMB
Product: Intel(R) RAID Controller SRCSAS18E with 2 Expander Backplanes
Disks: Seagate Barracuda ES.2 ST31000340NS Revision Level SN03 and SN04
OS: Windows* Server 2003 SP2

Fulco

An Interesting Problem:

I am installing the Seagate SATA ST3500320AS in a WinTel system running the Intel D865GBF motherboard (firmware revision P25), and no other expansion cards. The machine is a stand alone file server, running Windows Server 2003 with current patches.

Installation steps: physically install drive into unit. Leave Hard Drive jumper installed limiting data transfer rate to 150MB/s. Start unit. Using Physical Drive utilities in Windows Server, create a partition. I did not use the wizards' tool to format the drive.

From a command prompt, I formatted the drive using the command:

format d: /u/fs:ntfs/a:512

The format completed successfully.

USAGE AND FAILURE
I loaded the drive with data, and attempted to fill the drive to capacity (465GB). Drive performed fine until we reached ~ 120GB of capacity, and then the drive performance went to zero.

Specifically, using the Microsoft Performance monitor, I viewed the %ReadTime, %WriteTime, and AvgDiskQueueLen for the drive. When operating normally, these values fluctuated around small values, indicating good performance.

When the problems occurred, the %DiskWriteTime jumped to values beyond 2000, and the AvgDiskQueueLen value remained up around 18.

Attempting to reformat this drive using the default cluster size also produced the same results:

format d: /u/fs:ntfs

Any ideas why this is happening?

THANK YOU!

I don't know if your problem is related.

The 'slow write rate' problem is solved but:
I ended up replacing several Seagate disks for Hitachi ones.
Intel didn't help solve this issue.
I won't recommend anyone buying Intel Server hardware.
Maybe Intel VARs give better support: Intel doesn't support End User very well!!

I solved the issue by replacing the Intel RAID adapter for an Adaptec 5805.
This solved all the issues.

Fulco