RE: Accessing a file in memory

["Shaw, David" <dshaw@xxxxxxxxxxx>]

James,

The advantage of SETOBJACC is that it loads the entire contents of an object
into memory immediately (assuming it all fits), whereas if you rely on
normal I/O to bring it in it's pulled in a few pages at a time as page
faults occur.  If expert cache is turned on and there's sufficient memory to
work with it's "smarter" about the number of pages, but even so it's
probably not going to bring in the entirety of most database tables.
Cutting out the page faults while the program is processing is what gives
the SETOBJACC a performance advantage.

Note: This explanation is my simple-minded in-brain model, the real world is
likely to be considerably more complex. <grin>

Dave Shaw
Spartan International, Inc.
Spartanburg, SC

-----Original Message-----
From: James W. Kilgore [mailto:qappdsn@attglobal.net]

Patrick,

I read some of the other responses and started thinking (bad thing on a
Monday
;)), but if you have enough memory to place the files into memory, then why
aren't they staying in cache?  So I'm not sure if you have enough memory for
SETOBJACC to work for you.

AFAIK, user space is just space and may not reside in memory.  Remember,
under
single level storage disk and memory are the same thing.

If you don't have enough memory for SETOBJACC to work for you, I'm not sure
that
making the files into tables would help much either.  You may just be
changing
-what- is being swapped.

BTW, you mentioned that another company with the same software did it.  What
was
their improvement in through put and do you have a similar HW configuration?

As a last resort, does the software provider have any solutions?
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