poller.php multiple launched, eating up CPU


I wonder if the poller is really needed or if somehow the cron jobs can be executed without it? I had setup as it should be:

*/10 * * * * cd ${HOME}/friendica/htdocs/ && /usr/bin/php include/poller.php

If I let it runs, multiple php processes are forked eating up my CPU and slowing down the server. Currently it seems to work without it (and much faster).