Slow Throughput - Ultrium 1760 External Tape Drive

[Sean Curran]

Hi folks,

I'm getting really slow throughputs of approx 10Mb-75Mb/Min
the ext tape drive is connected via SAS to an adaptec 1045.

OS is WinXP Pro SP2, the ultrium is the only device attached via SAS to the SCSI card and using HP's Data Protector Express 4.00 SP1

I have ran the LTT performance tests and it always alerts me of very slow throughput.

Pulling my hair out, can anyone point me in right direction to sort this?

[TapeDrive Killer 1 2]

use LTT to generate a support ticket and attacht it here.

Pablo Alvarado Siles

[Richard Bickers]

There are two types of performance test in LTT to help tell where the problem is:
* Drive performance - will measure the rate from the back of your server to your drive
* System performance - will measure the rate at which data can be pulled from your disks

The drive performance test typically shows that the drive is running fine unless you've got an interface/HBA problem. If the drive is working at all it will normally be close to it's max speed anyway. The drive is very rarely the problem.

The system performance test will likely show that the bottleneck is with your disk IO. There's not much you can do other than beef up your disk system.

We added this test because it's a very common problem. People often don't realise how slow their disks are. It's take a lot of RAIDed disks to keep up with a modern tape drive.

See http://www.hp.com/support/pat for general performance advice.

As mentioned by Mr. Killer, the ticket will also show us a few details of what the drive thinks is going on.

Good luck.