It is imperative to your success that you read and follow the advice in the appropriate IBM Redpaper™ for your release:

IBM Business Process Manager V8.5 Performance Tuning and Best Practices

IBM Business Process Manager V8.0 Performance Tuning and Best Practices

IBM Business Process Manager V7.5 Performance Tuning and Best Practices

Also see 5 Things to Know About IBM BPM Performance Tuning.

Applicable editions: Express, Standard, and Advanced

Applicable releases: All

Source: IBM