Tape drive compression ratio

[Bill O'Brien_6]

I have a compaq 40/80 tape drive and arcserve software. I already asked arcserve support which was better - hardware or software compression. They stated hardware compression is better and that with hardware compression enabled software compression is off - which is my current configuration. My compression ratio is 4.45 - is this ratio adjustable and if so how??

[Sunil Sharma_1 · Accepted solution]

Hardware compression ration is not adjustable. Compression ration depends on the type of data you are backing up. It vary with the type of data change. Hardware compression either can be on or off there is no other choice. This can be acheived by DIP switch/Jumpers.

Sunil

[Marino Meloni_1]

here is a lot of info

http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=lpg50244

Marino

[Dave Wherry]

Another factor besides the data being backed up is the quality of the media and how clean the tape heads are. You can back up the same set of data to the same device and get radically different compression ratios with different media.
Even brand new tapes come out of the factory with some residue on them. That will eventually come off on the tape head. That gets removed with the cleaning cartridge. Over time the cleaning cartridge degrades the quality of the tape head. With use, the tapes degrades. The ratio will change.