QJOBSPLA setting

[David Fosdike]

Does anyone have experience with what changing the QJOBSPLA attribute
really does? The Work Management Guide (p45) states that the default
setting (3516 bytes) is good for up to 2 spool files per job. It also
says increasing it to 9600 bytes will be good for up to 8 spoolfiles.
The odd thing is, though, that it also says that the setting has no
bearing on processing performance. It also implies that changing the
default setting is not necessary even if more than 2 spool files are
required. So, what exactly does this setting do (the manual says 'this
value primarily affects auxilliary storage requirements'???) and under
what circumstances do I need to change it? We have about 36,000 jobs in
our system - an extra 6K for each would mean in excess of 200MB of
storage space used. Can this same effect, whatever it is, be achieved
on a job by job basis?

Thanx in advance,

David Fosdike
dfos...@nospam.elders.com.au

[Rodney Johnson]

David, My advice is to leave the system value at its default setting of
3516 (it will end up being 4K...minimum page size in risc hardware).

QJOBSPLA was created many years ago when storage on a system was at a
premium and was not cheap to buy and easier to max out. The system auto
extends the space when it needs to (about 25% of current size each time it
extends...rounded to nearest pages size of course). At one time, the
extension of spaces on the system was a rather expensive operation and was
suppose to be avoided as much as was practical. With todays processors,
performance with extending spaces is a nonissue for the most part. With
V5R1, the QSPSCB space (the object being discussed) nolonger is used to
store the attributes for spooled files of a job (one QSPSCB per job). It
rarely goes beyond the minimum object size of 4k (only i f you use inline
files in CL batch streams).

David Fosdike wrote:

--
Rodney A Johnson
Technical Team Lead for AS/400 Spool
Dept GJC
IBM Rochester, Minnesota

The contents of this message express only the sender's opinion.
This message does not necessarily reflect the policy or views of
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sender.

[David Fosdike]

Thanx Rodney

David Fosdike
dfos...@nospam.elders.com.au
Rodney Johnson wrote in message <3BF130A2...@rchland.ibm.com>...