Start logging bptm.  After your backups have completed, go through the log
file and see if there are large repetative delays.

1.  Waited for full buffer = data buffer size is too large
2.  Waited for buffer = too few buffers

If using DLT, I agree on the 64k buffer size replied to earlier.  Start with
64k and 8 data buffers and work up from there.

Matt Moody
MCSI


-----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 Tricia C.
Sesar
Sent: Monday, September 16, 2002 7:23 PM
To: Andy Skates; veritas-bu AT mailman.eng.auburn DOT edu
Subject: Re: [Veritas-bu] Memory allocation - Solaris 8


On Monday 16 September 2002 10:53, Andy Skates wrote:
> Being fairly new to Solaris (version 8), can someone answer a question
> for me?
>
> I have a NBU 4.5 Media Server (running on a Solaris 8 server). I want to
> change SIZE_DATA_BUFFERS to 262144 and NUMBER_DATA_BUFFERS to 32, to see
if
> this improves performance.
>
> This server has 3Gb of memory.
>
> I seem to remember someone saying that they is a configuration file within
> Solaris which states how much memory etc an application can use.
>
> If so, where is it, and what do I have to do to it to allow NBU to use as
> much memory as it requires?
>
>
> Thanks,
>
> Andy Skates
>
> andyskates AT iname DOT com

>From the technote that Mark pointed you to:

"NOTE: For Digital Linear Tape (DLT) drives the number that seems to give
the
best performance for SIZE_DATA_BUFFERS is 65536. Further performance
improvements can be achieved by increasing the value in the
NUMBER_DATA_BUFFERS file."

My own testing confirms this in my environment.
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