Exabyte autoloader and compression

[weescotty]

Equipment-
VXA-2 Packetloader 1x10 1U Autoloader.
Adaptec 2940U2W latest firmware and drivers.

Software-
Windows 2000 Server SP4 and all fixes/patches.
Arcserve 2000 v7 build 1100.

2 Issues -
1) Getting a throughput of 174mb/s, this a limit because of the SCSI card? If so would an Adaptec 29160 give better results?

2) How can tell if compression is being used. Read the FAQ but the compression option is greyed out in ArcServe. Last job showed 15Gb on disk, 16Gb on media if thats any help. The Exabyte has compression turned on by default. Both the Autoloader and the VXA-2 are correcly recognized in the ArcServe device manager.

Apart from these two things it works great.

Thanks.

 

[davidmichel]

The ARCserve CDL lists the drive as 80gb. So it looks like for some reason it does not support compression with the drive. Normally for compression drives it would list both values 80-160.

The as long as the controller is the bottleneck then yes it can be expected that the 29160 will provide better throughput.

 

[weescotty]

Thats what I thought...until-
You can change the ID of the VXA-2 to a Mammoth2 that is on the CDL.
Compression is still greyed out, wonder if this could be because it is on by default?
When I tried setting software compression I got an alert saying that it was disabled due to hardware compression.

 

[davidmichel]

One way to find out for sure, and that is to fill up a tape and see how much it takes to span.

 

[weescotty]

Funny you should mention that -
Just backed up 114Gb onto a singe 80/160 tape, so I guess hardware compression is working .

Got an average of 400+ mb/s throughput, I think using a giagbit switch may improve this for small files.

Thanks for all help.