[Veritas-bu] SDLT320 : ?REAL? native capacity

This is interesting. However, how does one change the block size in Netbackup? 
I know how to change the buffer sizes, but I can't find any hint with Google 
on changing the block size.

Anyone can comment on this?

Many thanks (again)!

On Wednesday 16 June 2004 1:32 pm, Len Boyle wrote:
> Hello
>
> You might try turning off hardware compression at the drive and see if they
> improves things. The data may be growing on the second compression pass.
>
> Also what is the block size you are using to write the data to tape. You
> have an inter-record gap between each block. The smaller the block size,
> the greater the number of inter-record gaps.
>
> len
>
> -----Original Message-----
> From: veritas-bu-admin AT mailman.eng.auburn DOT edu
> [mailto:veritas-bu-admin AT mailman.eng.auburn DOT edu]On Behalf Of Mathieu
> Nantel
> Sent: Wednesday, June 16, 2004 1:15 PM
> To: veritas-bu AT mailman.eng.auburn DOT edu
> Subject: [Veritas-bu] SDLT320 : ?REAL? native capacity
>
>
> Good day (again),
>
> I've recently been archiving pre-compressed data in bz2 format to tape. I'm
> quite certain that my SDLT drive's hardware compression is not as good as
> bz2, so there probably isn't too much compression going on.
>
> The reason I'm saying this is that I was able to fit a mere 142 gigs on a
> tape which is meant to have a NATIVE capacity of 160 gigs.
>
> This rose a few questions here. Is this analoguous to the way hard drive
> vendors count hard drive space in base 10 vs base 2 for computers? In this
> case, I shouldn't be loosing any more than 2.4% of the space (1000KB vs
> 1024KB). (142*100/160) tells me that I've got a 11.75% loss of space, which
> sounds a bit too much to me.
>
> Anyone can shed some light on this?
>
> Thanks,

-- 
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