Stack walking performance issue

Amir Hadadi amirhadadi at
Sun Mar 17 14:43:15 UTC 2019

We've encountered the following performance issue which happens on an instance deployed in docker with ubuntu 16.04, Linux kernel 4.4.0-92-generic and OpenJDK 11.0.2.
The issue shows up with zgc but does not show up with G1.

During a period of 10 days after deployment, CPU usage goes up steadily at a rate of ~10% per day. Eventually we have to restart all instances.
I profiled our app after 4 days of uptime using async-profiler and found that the following stack is the most frequent stack:
I tried restarting the instance and waited 10 minutes before profiling, and stack walking shows up much less in sampling:
This is how the stack walk looks when profiling an instance deployed with g1 after 3 days:

Please help me figure this one out.

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