Hi Everyone
I am working on bug https://bugs.openjdk.java.net/browse/JDK-8029346
Root cause for this bug is in CMS mode; gc could happen when
AllocatorThread is allocating spaces. in that case. objectPool won't be
added two object arrays as it's supposed to have. Also in that case. no
clear and gc will be invoked in SweepThread. Which means memory used is
still bigger than threshold. According the java doc. Subsequent crossing
of the usage threshold value does not cause further notification until
the memory usage has returned to become less than the usage threshold
value. That's the reason why next notification will never comes.
Suggested fix is making below change in doTask, make sure in every loop
two object arrays are added objectPool and gc will be invoked in
SweepThread.
change
while (!listenerInvoked) {
into
while (!listenerInvoked || mpool.getUsage().getUsed() <
mpool.getUsageThreshold()) {
Please let me know if you have any comments or suggestions.
Thank you
Tristan
