[CASSANDRA-15240] Reinstate support for native libraries for in-JVM dtests

• Type: Improvement
• Status: Triage Needed
• Priority: Normal
• Resolution: Unresolved
• Component/s: Test/dtest/java
• Platform: All
• Assignee: Unassigned
• Reporter: Jon Meredith
• Created: 19/Jul/19 19:45
• Updated: 27/Aug/20 15:10

Description

While working on CASSANDRA-15170 native libraries for libc functions, epoll support and openssl were observed holding gcroots to the instance class loaders when in-JVM dtest with(NETWORK) support was enabled. The solution for CASSANDRA-15170 was to disable native libraries to get everything working, but this is not ideal because in-JVM tests will not be testing the real code on that platform.

One proposed solution from ifesdjeen and benedict is to introduce an additional classloader per-Cassandra version that can be used for loading native libraries and share the CassandraVersionClassLoader by each instance of that version, enabling the InstanceClassLoader to be garbage collected.

CLibrary 
 com.sun.jna.Native.registeredClasses
 com.sun.jna.Native.options
 com.sun.jna.Native.registredLibraries

Netty
   io.netty.channel.ChannelException
   io.netty.channel.unix.DatagramSocketAddress
   io.netty.channel.unix.PeerCredentials

   io.netty.internal.tcnative.CertificateCallbackTask
   io.netty.internal.tcnative.CertificateVerifierTask
   io.netty.internal.tcnative.SSLPrivateKeyMethodDecryptTask
   io.netty.internal.tcnative.SSLPrivateKeyMethodSignTask
   io.netty.internal.tcnative.SSLPrivateKeyMethodTask
   io.netty.internal.tcnative.SSLTask