I have configured rsyslogd to write log files to an external drive.  When the service is not started, but the drive is mounted, my disk utilization (by df) is low.  As soon as I start rsyslogd, the disk utilization creeps up over a minute or so to very high utilization on the main drive (not the drive that it's logging to.)  Using du to try to find a cache file or something else that might be used by rsyslogd shows nothing.  What could be causing this?
rsyslogd taking up all my drive space, only when the service is started
rsyslog