## 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.