Tvheadend

Hi everybody,
i would like to know if there is a way to know (thru a script), if tvheadend is recording or streaming liveTV to a device !
My tvheadend + hdhomerun is running on a Synology NAS (ARM), and when uncompressing some big files or crypting some, tvheadend has not enough CPU Time to work properly (recording and liveTV is not smooth). I try to renice porcesses, but it seems not working.

So what i would like to do, is to stop some processes on tvheadend recording and liveTV.

regards