Slow ATAPI tape drive performance on ML350 G5

[CA714829]

I have a Proliant ML350 G5 with a Sony AIT-2 Turbo (SDX-560V) ATAPI tape drive running SBS 2003 and Backup Exec 11.0d. Tape backups are running extremely slow. The transfer rate is around 100MB/min. Similar SCSI and USB drives yield transfer rates around 500Mb/min. However, Sony's specs show 12Mb/sec for all 3.

I've set the drive to Master, Slave, and CS with no luck. I even disconnected the DVD drive so that the tape was the only device on the controller. The server is patched with the latest drivers (Support Pack 7.80) and firmware and the tape is running the latest Veritas drivers.

Any idea what the problem might be?

[Chris Rosan]

I've NEVER seen a tape drive live up to what the specifications say.

It depends on the file types, the software & driver you're using, the OS and a lot of other things.

Which drivers are you using? Backup exec or Sony's drivers? You can try changing the drivers.

Other than that you should probably look at buying a newer SCSI or SATA/SAS drive to increase the performance.

[Kedd Guyton]

I'd guess that the Sony spec's are 12Mb/s to show a minimum speed for USB 1.1.

Regardless, I'm going to suggest something that helps most folks get their IDE CD/DVD drives working more effectively. In Device Manager expand IDE ATA/ATAPI Controllers, and then open the properties of your Primary IDE Channel (or Secondary IDE Channel if the tape drive is connected to it). Click the Advanced Settings tab. Confirm that the Transfer Mode and Current Transfer Mode are set to DMA (not PIO Mode).

[CA714829]

Changing from PIO to DMA did the trick. It now backs up on par with SCSI and USB. Thanks for your help.