Range:0 or any integer in [60, 7200]
Rac:Multiple instances should use the same value.
Notes:ARCHIVE_LAG_TARGET limits the amount of data that can be lost and effectively increases the availability of the standby database by forcing a log switch after the specified amount of time elapses.A 0 value disables the time-based thread advance feature; otherwise, the value represents the number of seconds. Values larger than 7200 seconds are not of much use in maintaining a reasonable lag in the standby database. The typical, or recommended value is 1800 (30 minutes). Extremely low values can result in frequent log switches,which could degrade performance; such values can also make the archiver process too busy to archive the continuously generated logs.