Re: Reusing deleted records

I don't believe that this could be correct from what I understand the
relationship is between job ODP's and the underlying RDBMS.

In a layered OS like OS/400, any program can, through the feed back DS, know how
many other programs are using a particular file.  So I have to conclude that the
OS is aware of multi job interaction with a particular file.

I missed the original post so I'm going out on a limb here .... Does the program
perform record deletes and block adds?  The reason I ask is that if the disk
controller receives a record delete it will do so immediately (or appears to) 
but
blocked writes would be delayed and possibly be treated as a group that the
controller may attempt to search for a contiguous block write area.

So although the program may delete x records then write x records, if the delete
was through a logical, and the writes through a physical there is no 
relationship
to the deleted space (record numbers) and the attempted block write.

If this is the case, you would want to change the physical to force write on 
each
record add and sacrifice blocking.  That is if reusing deleted records is more
important than write performance and the necessary RGZPFM to reclaim disk space.

2 centavos (and dropping)

James W. Kilgore
qappdsn@ibm.net

>
>
> At 04:44 AM 9/21/98 -0400, you wrote:
>
> >You are correct.  When a file that specifies REUSEDLT(*YES) is opened, as a
> >part of the open, OS/400 develops the deleted records map.  When a record
> >is added under that file open OS/400 consults the deleted records map for
> >the RR# of where to add the record.  When all deleted records have been
> >exhausted, only then are new records added at the end of the file.  If
> >another job opens the file later and deletes a record, the first job will
> >not know about the newly deleted record until the file is closed and
> reopened.
>
>

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