4 Replies Latest reply: May 23, 2014 7:31 AM by mseberg RSS

    The lag between a primary and its stby, what does it really depend upon ? (active DG)



      We're on 11gR2 with active DataGuard replication between several RAC databases.

      We've noticed that for many DBs the lag (checked with a select on v$dataguard_stats)

      is fluctuating, growing up sometimes to more than an hour before reducing itself

      all of a sudden to a few minutes or seconds, it changes all the time (I mean for a given

      DB we don't keep a regular lag more or less constantly: it moves a lot).


      Yet these DBs incur transactions (not many, but this is permanent) all the while so I

      thought that the lag would never be bigger than, say, a few minutes...


      How can you explain this behaviour ?