Memory Leak On weblogic.rjvm.ConnectionManager Generating A High Rate Of Old Collections Making System Perform Poorly (Doc ID 1437125.1)

Last updated on NOVEMBER 16, 2023

Applies to:

Symptoms

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.

Main Symptoms:

• 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:

• CPU usage will look similar to the following screenshot.
  
• General memory consumption will look similar to this:
  
• GC ratios will show a pattern similar to this one:
  
• A GC log will show the following pattern:
  

Cause

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