2023-12 Bufferpool Check

Hi all! Welcome to the end-of-year goody that we traditionally hand out to guarantee you have something to celebrate at the end-of-year party!


All Db2 releases since the very beginning of time have used Buffer Pools and when Data Sharing came along in DB2 V4 Group Bufferpools got invented. Since then bufferpools have always been with us and sadly no-one seems to really care about them anymore!


When was the last time that you actually checked your local and group bufferpools? Have you really seen any problems? The fantastic thing about Db2 is that you can have 1000’s of problems occurring every second or two but it *still* just keeps on truckin’ !

Where to Begin?

I always like to begin at the beginning and so review where you are right now by downloading and running the SEGUS BufferPool Health check program! It is an extremely light weight tool that you must simply run *locally* on each and every member and it simply lists out what it finds as being bad, horrible or evil!

Old Advice

Refer to my “old” blog to see what you could/should be checking and how bad it can really get as well.

Whaddya get?

The BufferPool HealthCheck is a one step program that simply lists out whatever it finds as being not good. At the end of the documentation is a table listing out all the checks it does. There is one important check it does *not* do and that is the cross-check between all local bufferpool sizes and the initial size of the related group bufferpool. That is just a little bit too complex for some freeware!

Want more?

If the results help you or you are interested in more, then our SQL WorkLoadExpert for Db2 z/OS product has a new separate licensable Use Case – Buffer Pool which contains all the checks plus the GBP Initial size one.

How does it look?

In this screen shot you see the list of Bufferpools being looked at and do you notice the highlights on a couple of tabs? Those yellow stripes should tell you that Bufferpool simulation is on in these two buffferpools. Simulation is really really good, it came in with Db2 11 but most people missed the launch event! Check it out as it is really good but beware! Do not simulate three or more Bufferpools at the same time!

Order By?

The order that you see is the importance list. In my humble opinion this is the list of KPIs that should be worked on from top to bottom and there are more than on this screen grab!


On the right-hand side, we then show you which corrective action is required, if any, to get the bufferpool running better, faster and cheaper!

On the overview highlights we list out what is Good, Bad and Ugly with direct links down to the details. Here will also come a ranking and a highlighting of the Tab to drag your eyes to the problem children that you undoubtedly have!

Here finally is then the first “top down” view of all your local bufferpools so that you can quickly see the sizes and usage of your bufferpools

Naturally it all looks better in RL!

I would dearly love to hear from any of you who run this software and get before and after reviews! I am 100% sure that buffer pools and especially group buffer pools are simply being ignored these days!


Roy Boxwell