Re: scanning user space

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Hi Pete, Scott,

I don't know how big your iSeries is, but it would seem possible that some
of the IFS file A pulled into memory is still there when B or C starts
running, relieving them of having to get the data from disk.  Since you said
other jobs were running, this could become more significant if the other
jobs finish, leaving more RAM available.

Peter Dow
Dow Software Services, Inc.
909 793-9050 voice
909 793-4480 fax
909 522-3214 cell


From: "Scott Klement"
> > A.    43.4 seconds elapsed 3.0 seconds CPU time.
> > B.    20.4 seconds elapsed 2.6 seconds CPU time.
> > C.    4 seconds elapsed 2 seconds CPU time.
> > D.    210 seconds elapsed 89 seconds CPU time.
> >
> [SNIP]
> > Can anyone explain why C is better than A and B?
>
> Without seeing your code, it's a little difficult.
>
> Here's what I'm thinking, though, based on assumptions of how the code
> works:
>
> 1) You're reading the entire file in all cases.  As long as the amount
>      of data you're transferring exceeds the minimum amount of disk
>      that's normally transferred to memory, the speed should be about
>      the same for this part of the operation.