Can one determine whether heap is normal or large somehow from installed release [Windows]

[tushev]

I need to determine whether installed release is of normal- or large-heap type.

Is it possible somehow, for instance, from a release file?

[aahlenst]

@pshipton Do you know of any option? If not, would probably a good idea to add it to the version output.

[pshipton]

You can't tell from the release file output. The -version output does indicate "Compressed References" or not. The difference in the build is the directory structure contains either a compressedrefs directory or a default directory (default for 32-bit). Where exactly that is in the structure depends on whether it's Java 8 or Java 11+, and whether it's Windows or some other platform. On Windows the directory is in the jre/bin directory, or in bin if there is no jre directory.

You could open an issue at https://github.com/eclipse/openj9/issues to see about adding something to the release file, but note the OpenJ9 project is actively working on not having a separate large heap build. It's functional but not yet performant.

[tushev]

Thank you very much! This is enough for my task.

[tushev]

@pshipton Still need one more clarification - does default for 32-bit tells that it's normal heap?

i.e., the algorithm looks like:
if x64 => presence of compressedrefs = normal heap; default = large heap
if x32 => presence of default = normal heap

[pshipton]

Correct, there is only one type for 32-bit.

[tushev]

@pshipton Thank you!