cloudfoundry / java-buildpack

Cloud Foundry buildpack for running Java applications
Apache License 2.0
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Memory Calculator version #997

Open mayrstefan opened 1 year ago

mayrstefan commented 1 year ago

Is there a reason the Java Buildpack is still using Memory Calculator 3.13.x instead of 4.2.x? Are those versions not compatible?

mayrstefan commented 1 year ago

Okay, I see they use different cli parameters which is a breaking change. Are there any plans for an upgrade?

dmikusa commented 1 year ago

Yes, that is a reason.

Also, the 4.x branch was done before @pivotal-david-osullivan or I started working on the project and we have no context on the changes there. Why it was done, what advantages it has over 3.x, why did the cli flags change, etc... Since there's no context on the project anymore, we'd have to do a pretty extensive code and commit review before doing anything with it.

Is there something you are looking for that is in the 4.x branch but not in 3.x?

mayrstefan commented 1 year ago

I was just wondering what is going here. Also I found a reference to version 4.1 when looking around the Tanzu buildpack docs: https://docs.vmware.com/en/VMware-Tanzu-Buildpacks/services/tanzu-buildpacks/GUID-release-notes-graalvm-release-notes.html. Surprisingly this is only mentioned as a dependency in old versions of the GraalsVM buildpack. For paketo buildpacks the memory calculatore now seems to be part of the runtimes via a go dependency. We can find the calculator in https://github.com/paketo-buildpacks/libjvm/tree/main/calc

Maybe @nebhale can tell us what was the reason for the changes of the memory calculator