the Gemfire consultant add one more parameter to JVM

-Djava.nio.channels.spi.SelectorProvider=sun.nio.ch.EPollSelectorProvider

to be honest, I had no idea what it was. so I googled it.

the key things were Linux 2.6 system and handles lots of simultaneous connections

  from Oracle epoll blog and updated

So if you are running on a Linux 2.6 system with an application that handles lots of simultaneous connections you might want to give it a test-run. 

Will you see a difference? It depends on the workload. If you‘ve registered lots of SelectableChannels with a Selector and you notice a lot of time spent in the kernel due to poll then you should see a difference. If you are doing test runs and you want to do a direct comparison with poll then you can set the java.nio.channels.spi.SelectorProvider system property to sun.nio.ch.PollSelectorProvider. This will select the poll-based Selector that will continue to be the default on 2.4 kernels. There is an epoll patch for 2.4 kernels but at this time anyway, the NIO implementation doesn‘t attempt to detect this.

by the way, command to show the Linux Kerl uname -r