Document option -XX:[+|-]JITServerAOTCacheIgnoreLocalSCC

[cjjdespres]

Issue or pull request number:

Introduced in: https://github.com/eclipse-openj9/openj9/pull/18301 Made the default in: https://github.com/eclipse-openj9/openj9/pull/19585

Overview:

This was previously an undocumented experimental option in 0.44.0, but since it's now enabled by default in 0.46.0, it should be documented.

The option -XX:[+|-]JITServerAOTCacheIgnoreLocalSCC only has an effect when specified at a client of a JITServer, when that client is using the JITServer AOT cache mechanism. If enabled, the client will ignore its local shared classes cache when JITServer AOT cache compilations are performed. The client will still load classes and methods from its local SCC as appropriate; it will simply not otherwise look up or store information in the local SCC during JITServer AOT cache compilations. This allows the client to use the JITServer's AOT cache without having a suitable local SCC set up, but also means that the client will store few, if any, new methods in its local SCC.

If disabled, the client will look up and store data, including received cached methods, in its local SCC during JITServer AOT cache compilations. Clients disabling this option must have a local SCC set up in order to use the JITServer AOT cache.

Release target:

OpenJ9 0.46.0

Applies to the following JDK versions:

All supported JDKs

Applies to the following platforms:

All platforms supporting JITServer (Linux X|P|Z).

For new command line options:

• -XX:[+|-]JITServerAOTCacheIgnoreLocalSCC
• Default value: On