On Thu, Apr 24, 2003 at 09:26:12AM -0500, Russell Adams wrote:
> > Of course hardware compression has one big advantage: speed.  If you
> > have to fit lots of data in a small backup window at night, and your 
> > cpu's are not fast enough, or interfere with the nightly cpu-intensive
> > jobs, then hardware compression is the way to go.
> 
> 
> I have to take issue with this. My experience with hardware
> compression on DDS and DLT drives is that when enabled it makes things
> incredibly slow.
> 
> My DLT IV (er, 7000?) drives can do 4.9 MB/s uncompressed, and only
> 800KB/s in compressed mode.
> 

This is of course counter to advertising claims :))

Are you sure there was not some other factor involved.  A possibility
that comes to mind is that the no-hw-compression came from data already
in a single file or local to the server while the with-hw-compression
test data had to be "found" and that procedure caused the slow down?

-- 
Jon H. LaBadie                  jon AT jgcomp DOT com
 JG Computing
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