doc: add snooze_period doc to default.ini

Author: janl

rel/overlay/etc/default.ini

@@ -453,6 +453,12 @@ check_interval = 3600
 ; compaction will not happen. Very small files always have a very high
 ; fragmentation therefore it's not worth to compact them.
 min_file_size = 131072
+; With lots of databases and/or with lots of design docs in one or more
+; databases, the compaction_daemon can create significant CPU load when
+; checking whether databases and view indexes need compacting. The
+; snooze_period setting ensures a smoother CPU load. Defaults to
+; 3 seconds wait.
+; snooze_period = 3
 
 [compactions]
 ; List of compaction rules for the compaction daemon.