Richard,
IIRC the 16K tape blocksize was addressed years ago at which time IBM had no
intention of changing it.
If my memory is incorrect or a larger blocksize is indeed available, somebody
please enlighten me.
You might want to consider the following setsys parameters:
SETSYS -
TAPEHARDWARECOMPACT -
COMPACT(DASDBACKUP DASDMIGRATE NOTAPEBACKUP NOTAPEMIGRATE) -
Assuming your tapes have compaction enabled then there's no point in adding
software compaction.
I've also always used DUMPIO(4) which causes DFDSS Dump to read a cyl at a
time.
________________________________
From: Richard Marchant [mailto:[EMAIL PROTECTED]
Sent: Fri 3/16/2007 4:58 AM
To: [email protected]
Subject: HSM's Autobackup performance
Is there any parameters that can be tweaked to increase the performance
of HSM's autobackup?
A GTF trace shows that HSM backs-up datasets in 16K blocks.
Surely if HSM is using DFDSS as the datamover (default now) it should be
securing these datasets in 64K blocks at least.
Is it necessary to change any of the parameters in the DEVSUPxx member?
EG the COMPACT and TAPEBLKSZLIM
The HSM manuals have no information regarding the above.
Richard
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