Hi Chaps,
Just wanted to share my findings with you with regards to TSM compression/no
compression.
We have 3575-L18 tape library. We use 3570-C Format tapes. We used to have CLIENT
compression set to YES when doing backups, with DRIVE compression OFF. Most of the
data on our systems is Oracle. When we had client compression set to YES, each
cartridge would take about 5GB.
I have done some testing and found that when I switched compression OFF, we managed to
get around 21GB on each cart, and also the backups were a LOT quicker.
IBM recommend (and I quote:) "Oracle databases are normally full of white space, so
compression is required. Either h/w or client compression."
Could someone please explain WHY compression is required if we get more on tape with
it switched OFF, and the backups are quicker?.
In our environment, TSM has its own 10Meg a sec network, and 99.9% of the backups are
done overnight, so there is no problem with performance issues.
Am I missing something here, or is it REALLY a better idea to forget about compression
totally?.
Kind Regards,
Roy Lake
TBG European IT
Tel: 0208 526 8883
E-Mail: [EMAIL PROTECTED]
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