This is the blog of Ronald Bartels that wanders on and off the subject of problem management (that is how it started), but it is best described by Ray who says this is Daddy's thoughts! Like the best music is from the Eighties and a wee dram helps in solving most inconveniences.
LPAR2RRD - Free performance monitoring for VMware™ and IBM Power Systems™
The tool offers you end-to-end views of your server environment and can
save you significant money in operation monitoring and by predicting
utilization bottlenecks in your virtualized environment. You can also generate policy-based alerts, provide capacity reports and forecasting data. The tool supports IBM Power Systems™ and VMware™ virtualization platforms. It is agentless (it receives everything from the management stations like vCenter or HMC). Collected data set can be extended about data provided by the OS Agents or NMON files.
Download the tool from here or checkout a more comprehensive list of tools here.