Other people have given ideas about what could be happening but they haven't provided ways that you can check them.
The BMXAA7019I log entries will tell you the memory figures - so you can use those to check if lots of memory is being used up e.g. when the report server components are starting up.
The WebSphere console can be used to generate javacore files that provide details about the Java code that is being executed at a particular time. if you generate them at 20 second intervals then you can see what Java code is using the CPU - If you aren't experienced in analysing Javacore files then reach out to me and I can provide some analysis
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mark robbins
Cohesive
IBM Champion 2017-2024 Inclusive
See my blog on Maximo support related topics here:
https://www.linkedin.com/pulse/maximo-support-advice-from-non-ibm-engineer-article-mark-robbins/------------------------------