Configure the G1GC garbage collector

You must follow certain recommendations when switching from the currently used Concurrent Mark Sweep (CMS) GC to G1GC.

Recommended settings for G1GC
The recommended settings for configuring Garbage First Garbage Collector (G1GC) include allocating more Java heap space when compared to the Concurrent Mark Sweep (CMS) GC, and setting specific values for properties such as MaxGCPauseMillis and ParallelGCThreads.
Switching from CMS to G1GC
To move from Concurrent Mark Sweep (CMS) GC to Garbage First (G1) GC, you must update the HADOOP_NAMENODE_OPTS settings in hadoop-env.sh.

Parent topic: Data storage metrics