ZM_FILTER_EXECUTE_INTERVAL
ZoneMinder allows you to save filters to the database which allow events that match certain criteria to be emailed, deleted or uploaded to a remote machine etc. The zmfilter daemon loads these and does the actual operation. This option determines how often the filters are executed on the saved event in the database. If you want a rapid response to new events this should be a smaller value, however this may increase the overall load on the system and affect performance of other elements.