*** a/doc/src/sgml/backup.sgml --- b/doc/src/sgml/backup.sgml *************** *** 688,696 **** archive_command = 'test ! -f .../%f && cp %p .../%f' ! When archive_mode is off some SQL commands are optimized to avoid WAL logging, as described in . If archiving were turned on during execution of one of these statements, WAL would not contain enough information for archive recovery. (Crash recovery is unaffected.) For this reason, archive_mode can only be changed at server --- 688,698 ---- ! When archive_mode is off and is zero some SQL commands are optimized to avoid WAL logging, as described in . When streaming replication is disabled, ! if archiving were turned on during execution of one of these statements, WAL would not contain enough information for archive recovery. (Crash recovery is unaffected.) For this reason, archive_mode can only be changed at server *** a/doc/src/sgml/perform.sgml --- b/doc/src/sgml/perform.sgml *************** *** 910,933 **** SELECT * FROM x, y, a, b, c WHERE something AND somethingelse; ! Turn off <varname>archive_mode</varname> When loading large amounts of data into an installation that uses ! WAL archiving, you might want to disable archiving (turn off the ! configuration variable) while loading. It might be faster to take a new base backup after the load has completed than to process a large amount of incremental WAL data. ! But note that turning archive_mode on or off ! requires a server restart. ! Aside from avoiding the time for the archiver to process the WAL data, doing this will actually make certain commands faster, because they are designed not to write WAL at all if archive_mode ! is off. (They can guarantee crash safety more cheaply by doing an fsync at the end than by writing WAL.) This applies to the following commands: --- 910,938 ---- ! Turn off <varname>archive_mode</varname> and streaming replication When loading large amounts of data into an installation that uses ! WAL archiving or streaming replication, you might want to disable ! archiving (turn off the ! configuration variable) or replication (zero the ! configuration variable) while loading. It might be faster to take a new base backup after the load has completed than to process a large amount of incremental WAL data. ! But note that turning archive_mode on or off, ! and changing max_wal_senders require ! a server restart. ! Aside from avoiding the time for the archiver or the WAL sender to ! process the WAL data, doing this will actually make certain commands faster, because they are designed not to write WAL at all if archive_mode ! is off and max_wal_senders is zero. (They can ! guarantee crash safety more cheaply by doing an fsync at the end than by writing WAL.) This applies to the following commands: