JVM Tuning Summary (eight)-Typical configuration Example 2

Common Configuration Rollup

Heap Settings

-XMS: initial Heap Size

-XMX: Maximum Heap Size

-xx:newsize=n: Set Young generation size

-xx:newratio=n: Set the ratio between the younger generation and the older generation. For example, 3 means that the ratio of the younger generation to the older generation is 1:3, and the young generation takes up 1/4 of the younger generation and the older generation.

-xx:survivorratio=n: The ratio of the younger generation of Eden to the two survivor areas. Note that there are two survivor areas. such as: 3, said Eden:survivor=3:2, a Survivor district accounted for the entire young generation of 1/5

-xx:maxpermsize=n: Set Persistent generation size

Collector Settings

-XX:+USESERIALGC: Set serial collector

-XX:+USEPARALLELGC: Setting up a parallel collector

-XX:+USEPARALLEDLOLDGC: Setting up a parallel collector for older generations

-XX:+USECONCMARKSWEEPGC: Setting Up concurrent collectors

Garbage collection Statistics

-xx:+printgc

-xx:+printgcdetails

-xx:+printgctimestamps

-xloggc:filename

Parallel collector settings

-xx:parallelgcthreads=n: Sets the number of CPUs to use when the parallel collector collects. The number of parallel collection threads.

-xx:maxgcpausemillis=n: Set the maximum pause time in parallel collection

-xx:gctimeratio=n: Sets the percentage of time that garbage collection takes to run the program. Formula is 1/(1+n)

Concurrent collector Settings

-xx:+cmsincrementalmode: Set to incremental mode. Applies to single CPU situations.

-xx:parallelgcthreads=n: Sets the number of CPUs that the collection of concurrent collectors uses when collecting in parallel. The number of parallel collection threads.