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Is OpenJ9 write gc log asynchronously?

When use Eclipse OpenJ9 in docker container, can i put gc.log to NFS or Ceph?

I've read that OpenJDK write gc log synchronously: Is gc.log writing asynchronous? safe to put gc.log on NFS mount?.

Rick Gong
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Verbose GC logs could be directed to a file. The option is -Xverbosegclog (mentioned here https://www.eclipse.org/openj9/docs/gc/, although ATM most of Verbose GC documentation is still only on IBM website).

If you suspect that storage medium may block I/O operations, you can try using -Xgc:bufferedLogging. This isn't really documented option (no strong interest), but you are welcome to try it and let us know if you find it valuable.

Note however, with buffered logging, there will be a delay - with a sudden termination of JVM process, the logs may miss a few lines that were still in the internal buffer but not flushed to the file.

Aleks
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