Last updated on NOVEMBER 05, 2016
Applies to:Oracle WebLogic Server - Version 9.2 to 10.3.5
Information in this document applies to any platform.
Periodically, an environment gets caught in a cycle where several OC collections are happening in a row. Often it appears there should be plenty of available heap. When this happens, the server starts behaving poorly, showing several performance problems.
- CPU consumption in average around 35% to 40%.
- High Rate of Old Collections. (Around 250 -> 300 per 30 minutes) Note that any high rate of OC can be considered suspicious.
- Poor performance and excessive latencies appear on the environment.
To detect the symptoms, collect a JRockit Flight Recording and a heap dump for the troubled server. If a flight recording is collected, the following will be the expected behavior: