I/O Calibration

I/O Calibration is available in Oracle 11g database in the DBMS_RESOURCE_MANAGER package.  It's a read-only workload that running on one instance only but Oracle suggests that all instances in the cluster remain open to calibrate the workload across the enitre cluster.  The procedure requires the parameter inputs like the number of disks and maximum tolerated latency (ms).   

SQL> set serveroutput on
SQL> declare
  2  max_iops integer;
  3  max_mbps integer;
  4  actual_latency integer;
  5  begin
  6  dbms_resource_manager.calibrate_io (
  7  num_physical_disks => 16,
  8  max_latency => 10,
  9  max_iops => max_iops,
10  max_mbps => max_mbps,
11  actual_latency => actual_latency);
12  dbms_output.put_line ('IOPS = '|| max_iops);
13  dbms_output.put_line ('MBPS = '|| max_mbps);
14  dbms_output.put_line ('Latency = '|| actual_latency);
15  end;
16  /


select inst_id, status, calibration_time from gv$io_calibration_status;

   INST_ID STATUS        CALIBRATION_TIME
---------- ------------- ---------------------------------------------------------------------------
         2 IN PROGRESS   02-MAY-11 02.36.13.490 PM
         1 IN PROGRESS   02-MAY-11 02.36.13.490 PM


IOPS = 2873
MBPS = 138
Latency = 8


   INST_ID STATUS        CALIBRATION_TIME
---------- ------------- ---------------------------------------------------------------------------
         2 READY         02-MAY-11 02.46.55.321 PM
         1 READY         02-MAY-11 02.46.55.321 PM