Re: deleted records in file causing performance problem - HELP!!

I think that had the founding fathers of the System/38 had enough time and
money, REUSEDLT(*YES) would have been built in as a default.  It wasn't
added until V2R1M1 unfortunately.

Your only alternatives are:

1).   RGZPFM, which will take hours with the file off-line.  Lakeview sells
a product that allows for reorg while active.
2).   Change the file to REZUSEDLT(*YES), which will also take a long, long
time.  Then as more records are added to the file, they will fill up the
deleted spots.

Caution:

1).   REUSEDLT(*YES) can cause quirky performance, and in fact if they file
will never fill, then RGZPFM is the only alternative.
2).   Applications that are being written over files specifying
REUSEDLT(*YES) need to be sure that there is never any program that reads
the file sequentially that assumes that the record N+1 in the file was
always written after record N.  (If you didn't write the application, you
have no way of telling).  Also developing a new application over such a
file can prove trying, because when we add a record to a file, we are
trained to think that it's the last record in the file, which in a
REUSEDLT(*YES) situation it will not be.

The way that REUSEDLT(*YES) words is that when the file is open, a deleted
records table is created in the ODP of the job, and that table is used to
help inserting records.  If once the file is open another job creates a new
deleted record, the first job will never know about it.

Happy Fourth to Everybody!

Al

Al Barsa, Jr.
Barsa Consulting Group, LLC

400>390

914-251-1234
914-251-9406 fax

http://www.barsaconsulting.com
http://www.taatool.com


midrange-l-bounces@xxxxxxxxxxxx wrote on 07/01/2003 09:57:56 PM:

>
> I have a 30 million record file with 20% deleted records.
>
> Some users are experiencing delays (up to 1 minute) in a critical RPG
> interactive order entry program.
>
> I can't seem to find an IBM utility to help diagnose the error.
>
> I think the problem could be lots of deleted records in a file that the
> program is performing a SETLL on to check for record existence.
>
> I thought dspjob option 14 would reveal if the database is reading thru
> 1000's of deleted records, but apparently I cannot see that this is
> occurring, and which file is causing the problem.
>
> Is there any OS400 command to see my program reading thru thousands of
> deleted record slots?
>
> The file is set to reuse deleted records = *no.
>
>
> PS only one or two activation groups exist, so I dont think it is
building
> 1000's of those.
>
> Also, other AS/400 programs running on the same PC on different
> Client/access sessions are working fine.
>
> Thanks!!
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