to allow the transaction to commit asynchronously. However, the
special value <literal>local</> is available for transactions that
wish to wait for local flush to disk, but not synchronous replication.
+ If <varname>synchronous_standby_names</> is not set, <literal>on</>,
+ <literal>remote_write</> and <literal>local</> provide the same
+ synchronization level; transaction commit only waits for local flush.
</para>
<para>
This parameter can be changed at any time; the behavior for any