Message11600

So to narrow this down, I removed this statement from Lib/_socket.py:

NIO_GROUP = NioEventLoopGroup(_NUM_THREADS, DaemonThreadFactory("Jython-Netty-Client-%s"))

This deletion is obviously going to cause failures for any actual usage of the socket module, but for testing the import itself of the socket module, this changedoes stabilize the count of open files from lsof (at 40 on my OS X laptop).

One thought I have here is that we should upgrade to Netty 4.1.x from 4.0.x; in particular, this allows us to use Executors for Netty event loops, and in particular ForkJoinPool and on Java 8 the common pool (https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ForkJoinPool.html#commonPool--). We also get other benefits, at the cost of having to do the upgrade (but this needs to be done regardless). Netty 4.1 continues to work against Java 7, so this doesn't impact Jython 2.7 dependencies. This change may also reduce selector usage.

We may need to look at other cleanup as well.