What is Young generation heap size: -XX:MaxNewSize?

Usage:

You can set max heap size for the young generation:

-XX:MaxNewSizet=<young size>[unit] , where unit can be k,m,g for kilobytes, megabytes gigabytes or without prefix for bytes.

Examples:

Set MaxNewSize to 512 megabytes:

java -XX:NewSize =512m

Description:

According to Oracle’s documentation, one of the most important tuning options is the proportion of the heap reserved for the Young Generation. It is minimum size of young generation which is allocated at JVM startup.  By default, the maximum size of the YG is 1310 MB, and maximum size is unlimited.

Default Value:

Default value is Xmx/5

Errors:

None

Arguments related:

TODO link ParallelGCThreads, MaxGCPauseMillis , GCTimeRatio, MinHeapFreeRatio, MaxHeapFreeRatio, Xmx, Xms, MaxNewSize

Related Posts:

• Garbage collection tuning.
• Quick start on Java GC.
• Heap Options Affecting Generation Size

NOTE:

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