[CASSANDRA-18841] InstanceClassLoader leak in 5.0/trunk

• Type: Bug
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 4.1.4, 5.0-alpha2, 5.0, 5.1
• Component/s: Test/dtest/java
• Bug Category: Degradation - Resource Management
• Severity: Normal
• Complexity: Normal
• Discovered By: User Report
• Platform: All
• Since Version: 4.1-alpha1

Source Control Link

https://github.com/apache/cassandra/commit/8bfe0e5878c64ed25591aae50643187bc8ab7241

Test and Documentation Plan

Run ResourceLeakTest#looperTest after increasing the number of loops to 100 - without the patch, this will fail on 5.0 and trunk long before you get to 100 iterations.

With the patch, it should reach 100.

• Assignee: Doug Rohrer
• Reporter: Doug Rohrer

Authors

Doug Rohrer

Reviewers

Francisco Guerrero, Jon Meredith

• Created: 12/Sep/23 14:55
• Updated: 01/Nov/23 08:54
• Resolved: 15/Sep/23 20:17

Description

Something in the 5.0/trunk branches has caused an in-jvm dtest InstanceClassLoader leak - it appears to have something to do with the Mutual TLS Authenticator (f078c02cb58bddd735490b07548f7352f0eb09aa) but nothing in that commit, so far, has stood out as causing issues.

The culprit class appears to be io.netty.util.internal.InternalThreadLocalMap, which seems to no be removed when the threads stops for some reason.

Issue Links

• links to: GitHub Pull Request #2686