RE: Performance Degradation after 7.5 upgrade

[Greg Wilburn <gwilburn@xxxxxxxxxxxxxxxxxxxxxxx>]

Should have mentioned that I've already done this... 
I built some indexes that were well-used.

We haven't IPL'd for a few weeks.

The select I did in RSS which took almost 2 minutes ran in 26 milliseconds directly thereafter.
Again - I was accessing the data by selecting "where" on two key fields.

That's why this seems odd.

-----Original Message-----
From: MIDRANGE-L <midrange-l-bounces@xxxxxxxxxxxxxxxxxx> On Behalf Of x y
Sent: Wednesday, September 20, 2023 1:30 PM
To: Midrange Systems Technical Discussion <midrange-l@xxxxxxxxxxxxxxxxxx>
Subject: Re: Performance Degradation after 7.5 upgrade

It's possible SQL is busy rebuilding MTI's.  After I re-IPL, there's a
significant performance hit for the first few transactions of a
database-intensive app, and then performance gets back to normal. Check
your Index Advisor to see what's being built, watch the Index Advisor for
the next few days, and make permanent indexes based on SYSIXADV.

On Wed, Sep 20, 2023 at 8:58 AM Greg Wilburn <
gwilburn@xxxxxxxxxxxxxxxxxxxxxxx> wrote:

> We are experiencing significant performance issues after our upgrade from
> 7.3 to 7.5 of OS/400.  We have the latest cume installed.
> The performance issues seem to be directly related to database access -
> both SQL and legacy applications.
>
> I just ran a simple query from Run SQL scripts directly selecting 5 rows
> from a large file, using the same keys as an existing logical file.
> It took almost 2 minutes to return the data.
>
> There are dozens of examples I've seen over the previous weeks since the
> upgrade.
>
> I'm not asking for possible solutions without providing more info... Just
> asking if anyone else has experience this?  Are there known issues with
> database response times?
> (i.e. qsys2.user_info_basic)
>
> TIA,
> Greg
> [Logo]<https://www.totalbizfulfillment.com/>    Greg Wilburn
> Director of IT
> 301.895.3792 ext. 1231
> 301.895.3895 direct
> gwilburn@xxxxxxxxxxxxxxxxxxxxxxx<mailto:gwilburn@xxxxxxxxxxxxxxxxxxxxxxx>
> 1 Corporate Dr
> Grantsville, MD 21536
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