i set --idle_timeout=15 as param, threads count and memory usage always grow, i got a heap dump and found many netty HashedWheelTimer instances cost much memory.
in HashedWheelTimer javadoc, it says: "Do not create many instances. HashedWheelTimer creates a new thread whenever it is instantiated and started. Therefore, you should make sure to create only one instance and share it across your application. One of the common mistakes, that makes your application unresponsive, is to create a new instance in ChannelPipelineFactory, which results in the creation of a new thread for every connection.". but in infinispan NettyChannelPipelineFactory.scala, there is "timer = new HashedWheelTimer", it's misused.