Memory leak in `ArrayRetainableByteBufferPool$RetainedBucket`

[KGOH]

Jetty version(s) 11.0.17

Java version/vendor openjdk version "21.0.3" 2024-04-16 LTS OpenJDK Runtime Environment Temurin-21.0.3+9 (build 21.0.3+9-LTS) OpenJDK 64-Bit Server VM Temurin-21.0.3+9 (build 21.0.3+9-LTS, mixed mode, sharing)

OS type/version Inside of a eclipse-temurin:21-alpine docker container

Description On several (not all) different instances of my application that are using the same functionality I observe a constantly growing direct memory usage (the saw-tooth pattern is due to manual application restarts)

I created a heap dump using jmap -dump:format=b,file=heap.hprof $PID. I inspected it with VisualVM and Eclipse MAT and both point to org.eclipse.jetty.io.ArrayRetainableByteBufferPool$RetainedBucket

Here are screenshots from VisualVM and Eclipse MAT from the dump inspection:

How to reproduce? 🤷