F.24. old_snapshot
  The
  
   old_snapshot
  
  module allows inspection
  of the server state that is used to implement
  
   old_snapshot_threshold
  
  .
 
F.24.1. Functions
- 
     
      pg_old_snapshot_time_mapping(array_offset OUT int4, end_timestamp OUT timestamptz, newest_xmin OUT xid) returns setof record
- 
     Returns all of the entries in the server's timestamp to XID mapping. Each entry represents the newest xmin of any snapshot taken in the corresponding minute.