[syslog-ng] RSS memory grows when disk is full

Hi, We are currently using syslog-ng version 3.3.6 . We are observing RSS memory growing issue for syslog-ng when destination disk is full. Is that an expected behavior , as the incoming message gets queued up in system RAM and thus RSS also will grow for syslog-ng process. Please correct me if I am wrong in understanding the same. Thanks, Arnob