AIT3 vs AIT4 - why did I slow down when upgrading? 1

[jbigbryw]

I recently changed out my Sony AIT3 tape drive for a Sony AIT4 drive in order to get more tape capacity. They appear to have almost identical specs and I have them configured the same way in regard to termination, compression, etc. However, when I first put the new drive in, throughput dropped to 25% of what it used to be. Upon doing some tweaking by upping the buffers to 30, cleaning up the volumes, etc. I was able to get that up to 50% of past throughput. This isn't letting me get the job through during my backup window.

My question is, why would the tape drive make such a difference? They are basicaly the same drive. How could it affect performance so much? Am I missing something (besided my sanity?)

 

[jbigbryw]

Just to update you, this is on a Novell 6 server using Arcserve 9.01.

 

[vschumpy]

The article below discusses LTO tape technology, but a similar situation may be applicable to your AIT environment :

http://www.techworld.com/storage/features/index.cfm?featureid=1125&Page=1&pagePos=11

I don't know what the max/min I/O speeds are for the AIT drives, you might wanna see if this is relevant.