What is Memory tuning: -XX:UseCompressedOops?

Usage:

You can disable the use of compressed pointers with:

-XX:UseCompressedOops.

Description:

    Disables the use of compressed pointers. By default, this option is enabled, and compressed pointers are used. This will automatically limit the maximum ergonomically determined Java heap size to the maximum amount of memory that can be covered by compressed pointers. By default this range is 32 GB.

    With compressed oops enabled, object references are represented as 32-bit offsets instead of 64-bit pointers, which typically increases performance when running the application with Java heap sizes smaller than the compressed oops pointer range. This option works only for 64-bit JVMs.

It's possible to use compressed pointers with Java heap sizes greater than 32 GB.

Default Value:

Enabled by default

Errors:

None

Arguments related:

TODO link Xmx, Xms, ObjectAlignmentInBytes

 Related Posts:

• Garbage collection tuning
• Garbage collectors documentation
• Tuning JVM

NOTE:

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