blackdrag commented on code in PR #2798: URL: https://github.com/apache/groovy/pull/2798#discussion_r3809459596
########## src/spec/doc/guide-integrating.adoc: ########## @@ -378,6 +378,43 @@ stub generation is done, for the joint compiler. However, overriding `CompilationUnit` is not recommended and should only be done if no other standard solution works. +== Class loader release in managed environments + +Applications that load and discard Groovy repeatedly — a web container performing (parallel) +redeployments with Groovy inside each web application, plugin systems, or any host that expects +class loaders to be garbage collected — need one extra consideration. + +Groovy associates runtime metadata (`ClassInfo`) with every class it dispatches on, including +JDK classes such as `String`. By default those associations use `java.lang.ClassValue`, which +gives the fastest possible lookup, but a long-standing JVM issue +(https://bugs.openjdk.org/browse/JDK-8136353[JDK-8136353]) prevents such associations on +long-lived classes from ever releasing their value — and with it the Groovy class loader the +value belongs to. In a container this shows up as metaspace growth on every redeployment, even +after the old application is undeployed. + Review Comment: +1 -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
