system uses too much cpu after upgrade

[Migrated content. Thread originally posted on 27 October 2011]

Hi

We upgraded our cobol system from server express 4.2 with oracle precompiler 9 to server express 5.1 with oracle precompiler 11g.

After the upgrade, the system uses 3 times more CPU.

Our system works on AIX 6.3.

Does anyone have an idea what could cause this problem?

As an outside observer I would suggest, if possible, changing one variable at a time. Is it possible to use the same preprocessor and try jumping up on the Server Express? Then if that is OK try upping the precompiler.

Also, I suspect you may have upgraded to AIX6.3 since Server Express 4.2 isn't likely to be supported on that platform. Lots of changes. No doubt this may explain the fact you have no response.

[Migrated content. Thread originally posted on 27 October 2011]

Hi

We upgraded our cobol system from server express 4.2 with oracle precompiler 9 to server express 5.1 with oracle precompiler 11g.

After the upgrade, the system uses 3 times more CPU.

Our system works on AIX 6.3.

Does anyone have an idea what could cause this problem?

Agreed - there are too many variables in play to guess at a possible cause.

My recommendations:

- As Greg suggested, if you can try the old Oracle preprocessor, that would help isolate the problem.

- Do some profiling to see where the application hotspots are. IBM's AIX documentation set includes a performance analysis and tuning guide (I've forgotten the exact title) with a lot of good information.

- Take a look at the performance-programming guide in the COBOL docs. It's possible that your application is doing something that causes unnecessary overhead, and that this has more of an effect in 5.1 than it did in 4.2. Sometimes fixes and enhancements create more overhead for sub-optimal programming constructs, since we generally try to optimize the preferred ones.