diff --git a/doc/src/sgml/postgres-fdw.sgml b/doc/src/sgml/postgres-fdw.sgml index b43d0aecba..23743435e0 100644 --- a/doc/src/sgml/postgres-fdw.sgml +++ b/doc/src/sgml/postgres-fdw.sgml @@ -460,11 +460,11 @@ OPTIONS (ADD password_required 'false'); Transaction Management Options - When multiple remote (sub)transactions are involved in a local - (sub)transaction, by default postgres_fdw commits - those remote (sub)transactions one by one when the local (sub)transaction - commits. - Performance can be improved with the following option: + When multiple remote transactions or subtransactions are involved in a + local transaction (or subtransaction) on a foreign server, + postgres_fdw by default commits those remote + transactions serially when the local transaction commits. Performance can be + improved with the following option: @@ -473,27 +473,25 @@ OPTIONS (ADD password_required 'false'); parallel_commit (boolean) - This option controls whether postgres_fdw commits - remote (sub)transactions opened on a foreign server in a local - (sub)transaction in parallel when the local (sub)transaction commits. - This option can only be specified for foreign servers, not per-table. - The default is false. + This option controls whether postgres_fdw commits in + parallel remote transactions opened on a foreign server in a local + transaction when the local transaction is committed. This setting + applies to remote and local substransactions. This option can only be + specified for foreign servers, not per-table. The default is + false. - If multiple foreign servers with this option enabled are involved in - a local (sub)transaction, multiple remote (sub)transactions opened on - those foreign servers in the local (sub)transaction are committed in - parallel across those foreign servers when the local (sub)transaction - commits. + If multiple foreign servers with this option enabled have a local + transaction, multiple remote transactions on those foreign servers are + committed in parallel across those foreign servers when the local + transaction is committed. - For a foreign server with this option enabled, if many remote - (sub)transactions are opened on the foreign server in a local - (sub)transaction, this option might increase the remote server's load - when the local (sub)transaction commits, so be careful when using this - option. + When this option is enabled, a foreign server with many remote + transactions may see a negative performance impact when the local + transaction is committed.