diff --git a/doc/src/sgml/maintenance.sgml b/doc/src/sgml/maintenance.sgml
index fe1e0ed2b3d..616aece6c0e 100644
--- a/doc/src/sgml/maintenance.sgml
+++ b/doc/src/sgml/maintenance.sgml
@@ -526,19 +526,23 @@
The sole disadvantage of increasing autovacuum_freeze_max_age>
- (and vacuum_freeze_table_age> along with it)
- is that the pg_xact> subdirectory of the database cluster
- will take more space, because it must store the commit status of all
- transactions back to the autovacuum_freeze_max_age> horizon.
- The commit status uses two bits per transaction, so if
- autovacuum_freeze_max_age> is set to its maximum allowed
- value of two billion, pg_xact> can be expected to
- grow to about half a gigabyte. If this is trivial compared to your
- total database size, setting autovacuum_freeze_max_age> to
- its maximum allowed value is recommended. Otherwise, set it depending
- on what you are willing to allow for pg_xact> storage.
- (The default, 200 million transactions, translates to about 50MB of
- pg_xact> storage.)
+ (and vacuum_freeze_table_age> along with it) is that
+ the pg_xact> and pg_commit_ts
+ subdirectories of the database cluster will take more space, because it
+ must store the commit status and (if track_commit_timestamp> is
+ enabled) timestamp of all transactions back to
+ the autovacuum_freeze_max_age> horizon. The commit status uses
+ two bits per transaction, so if
+ autovacuum_freeze_max_age> is set to its maximum allowed value
+ of two billion, pg_xact> can be expected to grow to about half
+ a gigabyte and pg_commit_ts to about 20GB. If this
+ is trivial compared to your total database size,
+ setting autovacuum_freeze_max_age> to its maximum allowed value
+ is recommended. Otherwise, set it depending on what you are willing to
+ allow for pg_xact> and pg_commit_ts> storage.
+ (The default, 200 million transactions, translates to about 50MB
+ of pg_xact> storage and about 2GB of pg_commit_ts>
+ storage.)