diff options
| -rw-r--r-- | doc/src/sgml/high-availability.sgml | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/doc/src/sgml/high-availability.sgml b/doc/src/sgml/high-availability.sgml index a7e2474189d..40b8b7393f8 100644 --- a/doc/src/sgml/high-availability.sgml +++ b/doc/src/sgml/high-availability.sgml @@ -947,7 +947,7 @@ synchronous_replication = on <para> After a commit record has been written to disk on the primary the WAL record is then sent to the standby. The standby sends reply - messages each time a new batch of WAL data is received, unless + messages each time a new batch of WAL data is written to disk, unless <varname>wal_receiver_status_interval</> is set to zero on the standby. If the standby is the first matching standby, as specified in <varname>synchronous_standby_names</> on the primary, the reply @@ -1013,6 +1013,12 @@ synchronous_replication = on the rate of generation of WAL data. </para> + <para> + Replies are only sent when WAL is written to disk, so setting + <varname>fsync</> to <literal>off</> on the standby will significantly + reduce performance of synchronous replication and should be avoided. + </para> + </sect3> <sect3 id="synchronous-replication-ha"> |