RE: Performance tuning -- MIDRANGE-L

One more item I forgot to mention.
In the early 2000's, we paid IBM big bucks (5 digits) to review our performance issue(s).
After a week of review, bottom line was we (3rd party application) had way too many access paths.
Either pay to have the app re-engineered or buy a bigger machine and simply mask the issue.
We bought a bigger machine.

Paul

-----Original Message-----
From: MIDRANGE-L [mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of Steinmetz, Paul
Sent: Friday, November 30, 2018 2:08 PM
To: 'Midrange Systems Technical Discussion'
Subject: RE: Performance tuning

1) You can start by turning on IBM performance adjustment.
I've been running at 2.
wrksysval QPFRADJ

Performance adjustment . . . : 2 0=No adjustment
1=Adjustment at IPL
2=Adjustment at IPL and automatic
adjustment
3=Automatic adjustment

2) Identify any bottle necks, CPU, Memory, DASD.

Years back, we had a memory issue, which resulted in excessive disk paging, which in turn caused our disks to be busy/overloaded. (found and confirmed by MPG)
We added memory, most issues went away.

Since then, our batch jobs were taking way too long, disk was the bottleneck.(found and confirmed by MPG)
Upgraded from 15k spinny drives to 100% SSD.
Batch jobs improved by 400%

3) Turn on Collection Services, if not running already.
Go perform
To check the status

2. Collect performance data
Collection Services status:
Status . . . . . . . . . . . . : Started
Collection object . . . . . . . : Q334000002
Library . . . . . . . . . . . : QPFRDATA
Started . . . . . . . . . . . . : 11/30/18 00:00:02
Default collection interval . . : 00:05:00
Retention period . . . . . . . : 01 day 00 hours
Cycle time . . . . . . . . . . : 00:00:00
Cycle interval . . . . . . . . : 24
Collection profile . . . . . . : *STANDARDP

Select one of the following:

1. Start Performance Collection
2. Configure Performance Collection
3. End Performance Collection

Also, I most change the default interval from 15 minutes to 5 minutes.
2. Configure Performance Collection

Default interval . . . . . . . . 05.00 *SAME, .25, .50, 1.0, 5.0...
Collection library . . . . . . . QPFRDATA Name, *SAME
Default collection profile . . . *STANDARDP *SAME, *MINIMUM, *STANDARD...
Cycle time . . . . . . . . . . . 000000 Time, *SAME
Cycle interval . . . . . . . . . 24 *SAME, 1-24 hours
*MGTCOL retention period:
Number of units . . . . . . . 00024 *SAME, 1-720, *PERM
Unit of time . . . . . . . . . *HOURS *HOURS, *DAYS
Enable system monitoring . . . . *NO *SAME, *YES, *NO
Create historical data . . . . . *NO *SAME, *YES, *NO
Create standard database files *YES *SAME, *YES, *NO

3) Finally, once you have data from collection services, there various tools, IBM and 3rd party, to assist in analyzing the data.
I've been using MPG from Midrange Performance Group for 15 years.
They offer a demo, and their support is top notch.
MPG has a neat feature, compresses the performance data for archival purposes.
We have 15 years of performance data available for review when needed.
Only takes a small amount of disk space.

Paul

-----Original Message-----
From: MIDRANGE-L [mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of Joe Pluta
Sent: Friday, November 30, 2018 1:09 PM
To: Midrange Systems Technical Discussion
Subject: Performance tuning

How do folks here analyze and tune their IBM i systems? I'm looking for
broad recommendations as to:

1. Do it myself? Are there enough tools available in the base O/S to do
so, and where would I start?

2. Additional IBM i licensed program options that would help with option 1.

3. Third party utilities. I have no idea if these exist; a cursory
Google turned up nothing.

4. Third party consulting.

Please note that I don't want to use David's list to solicit for
services. I'm just trying to get a feel for how it's done. The last
box I tuned was a model 270 and things have evolved a little since
then. If, though, you are someone who wishes to throw a hat in the ring
(yours or someone else's) then please feel free to send me an email
directly.