We've never heard of that issue. There's a ton of performance optimizations in JFBConnect and on standard page loads, JFBConnect does very, very little. It's only during the authentication process that JFBConnect does it's heavy lifting of connecting to 3rd party sites, downloading avatars, etc.
The grep they've done above is very vague as to what's going on. If they can provide a full log of strace.1423190672.log, that may help us narrow things down. With what they provided, it only indicates that a file from within the /com_jfbconnect directory was executed. It doesn't indicate any performance problem by itself as we'd expect files from that directory to be executed.
They should be able to give you very specific information on page load and server CPU times.
One other test to run is to simply disable the JFBCSystem plugin. That turns off all features of JFBConnect and is an excellent way to determine if there's a big performance improvement on your page. If so, let us know the difference (there are plenty of tools to measure rendering time like gtmetrix.com). If not, it means that JFBConnect is not the performance problem.
I hope that helps,
Alex
Hosting says: Jfbconnect plugin high CPU usage
