A streaming replica waiting on WAL from the master will wake up every 5 seconds to check for a trigger file. This is pointless if no trigger file has been configured.
The attached patch suppresses the timeout when there is no trigger file configured.
Rebased over the removal of recovery.conf and renaming of TriggerFile.
If the promote_trigger_file param is someday made responsive to SIGHUP, I think this will just continue to do the right thing without further modification.