Hi there, I've recently migrated a medium sized cluster (15TB, 25B documents) from 6.8 to 7.8.0 and noticed the heap constantly fluctuates between <1GB and the maximum set size (22GB). However the cluster is working perfectly fine and is noticeably faster after the upgrade, so I decided to let it g…

What can cause heap size to fluctuate wildly (hacksaw graphs) on a new 7.8.0 cluster?

Kim-Kruse-Hansen (Kim Kruse Hansen) August 7, 2020, 1:56pm 4

If you are using default jvm.options, you will be using new g1gc garbage collector on 7.8.x

Might check which gc, you are using
Regards

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