On WebClient I set the following option, but the executor still starts:
webClient.getOptions().setJavaScriptEnabled( false )
The DefaultJavaScriptExecutor runs a loop with Thread.sleep(10ms) that has impact on performance.
The executor should use other mechanisms instead of the costly loop with Thread.sleep to wake when there are jobs pending.

Note that this executor has top usage in my java profiler's hot spots.

htmlunit-2.36.0-SNAPSHOT