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Showing posts from February, 2013

Oracle PGA Memory Usage ,input output Usage query ,background process

SELECT   mymodule "Module", SUM (cpu_time) "CPU Time", SUM (wait_time) "Wait
Time",
         SUM (cpu_time) + SUM (wait_time) "Total Time"
    FROM (SELECT a.module mymodule,
                 (CASE (session_state)
                     WHEN 'ON CPU'
                        THEN wait_time / 100
                  END
                 ) cpu_time,
                 (CASE (session_state)
                     WHEN 'WAITING'
                        THEN time_waited / 100
                  END
                 ) wait_time
            FROM dba_hist_active_sess_history a, dba_hist_snapshot b
           WHERE b.end_interval_time > sysdate-10
             AND a.snap_id = b.snap_id
             AND a.user_id NOT IN (0, 5)
             AND a.instance_number = b.instance_number)
GROUP BY mymodule
  HAVING SUM (cpu_time) + SUM (wait_time) > 0
ORDER BY 2 DESC;


select
                 decode(n.wait_class,'User I/O','User I/O',

location of trace file

exec DBMS_MONITOR.SESSION_TRACE_ENABLE(waits => TRUE, binds => TRUE);

select value from v$diag_info where name='Default Trace File';

select u_dump.value || '/' || instance.value || '_ora_' || v$process.spid
|| nvl2(v$process.traceid, '_' || v$process.traceid, null ) || '.trc' "Trace File"
from V$PARAMETER u_dump
cross join V$PARAMETER instance
cross join V$PROCESS
join V$SESSION on v$process.addr = V$SESSION.paddr
where u_dump.name = 'user_dump_dest'
and instance.name = 'instance_name'
and V$SESSION.audsid=sys_context('userenv','sessionid');


exec DBMS_MONITOR.SESSION_TRACE_DISABLE;

Starting background process GTX4 and GLOBAL_TXN_PROCESSES

Starting background process GTX4 Tue Jan 01 15:51:12 2012 GTX4 started with pid=64, OS id=11122 Tue Jan 01 15:51:43 2012 Auto-tuning: Starting background process GTX5 and

Auto-tuning: Shutting down background process GTXi Like messages in alert log in RAC database
This event is recorded in RAC environment only, which is normal.  Its normal for the database to automatically tune the number of these processes based on the workload of XA global transactions. If any application which using XA transaction and connecting to oracle RAC database, is it required. This normal behavior and you do not have to worry about this error messages.  If you are sure that you are not using XA and want to stop these messages. You can disable the GTXn background processes, then you must set GLOBAL_TXN_PROCESSES to 0 in your parameter file. Setting this parameter to 0 will disable the XA support on an Oracle RAC database. GLOBAL_TXN_PROCESSES specifies the initial number of GTXn background processes (GTX0, ... GTX9 a…