We are seeing constant file descriptor increase on some of our Java gateway (see descriptor graph)
This increase in descriptors correlates with Java gateway stopping data collection once the descriptor count peaks.

Java gateway version: 4.2.8

Java version:
java -version
openjdk version "1.8.0_262"
OpenJDK Runtime Environment (build 1.8.0_262-b10)
OpenJDK 64-Bit Server VM (build 25.262-b10, mixed mode)

Additional JARs:
jboss-client.jar-21.0.1 (recently upgraded version)

We attempted to alleviate the issue with:

-XX:MaxDirectMemorySize=512m
-Dsun.rmi.transport.connectionTimeout=1000

This did not improve the behavior in any way.