2 Replies Latest reply: Apr 27, 2012 9:15 AM by 793965 RSS

    pga_aggregate_target

    793965
      hi gems...

      In the Oracle 11gr2 administrator's guide documentation, chapter Part1. 6. Managing memory, I read..

      "You
      can omit the statements that set these parameter (PGA_AGGREGATE_TARGET) values to zero and
      leave either or both of the values as positive numbers. In this case, the
      values act as minimum values for the sizes of the SGA or instance
      PGA."


      But at the end of the chapter, I read...

      "You can control this amount by setting the
      initialization parameter PGA_AGGREGATE_TARGET. Oracle Database then tries to ensure
      that the total amount of PGA memory allocated across all database server processes
      and background processes never exceeds this target."



      These two lines are opposing each other...please make it clear to me...thanks in advance..
        • 1. Re: pga_aggregate_target
          Oceaner
          hi gems...
          
          In the Oracle 11gr2 administrator's guide documentation, chapter Part1. 6. Managing memory, I read..
          
          "You
          can omit the statements that set these parameter (PGA_AGGREGATE_TARGET) values to zero and
          leave either or both of the values as positive numbers. In this case, the
          values act as minimum values for the sizes of the SGA or instance
          PGA."
          But at the end of the chapter, I read...
          
          "You can control this amount by setting the
          initialization parameter PGA_AGGREGATE_TARGET. Oracle Database then tries to ensure
          that the total amount of PGA memory allocated across all database server processes
          and background processes never exceeds this target."
          
          These two lines are opposing each other...please make it clear to me...thanks in advance..
          Yes its correctly written in the documentation.....But first part and second part are different in the context of the way SGA is managed...Means if you are managing your SGA with AMM (Automatic Memory Management) then first one is correct ....If you are managing your SGA with ASMM or manually (Setting SGA_MAX_SIZE or SGA_TARGET), then second statement holds true.
          • 2. Re: pga_aggregate_target
            793965
            okk sir...now i got the point...thanks a lot for your explanation... :) :)