[Oracle-l] dbms_resource_manager.calibrate_io, strange numbers

Hi,

To enable auto dop on a new system, I ran the calibrate_io procedure from the dbms_resource_manager package.
However the results are a bit strange.
The actual latency is reported as 0 and so is the max_mbps.
The max_pmbps however is set to 186.

Monitoring with collectl showed network troughput of arround 230 MB/s

Db version is 11.2.0.2 (64bit) on OL 5.4 (64bit).
Storage is NetApp, accessed via dNFS (using 2 1 Gbit/s connections)

I searched MOS and google, but no real bugs popped up.
What can explain the actual latency and the max_mbps to be set to 0?


SQL> @io_callibration.sql
SQL> set serveroutput on
SQL> set timing on
SQL> set echo on
SQL>
SQL> DECLARE
2
3 l_actual_latency integer;
4 l_max_iops integer;
5 l_max_mbps integer;
6
7 BEGIN
8
9 dbms_resource_manager.calibrate_io
10 ( num_physical_disks => 30,
11 max_latency => 20,
12 max_iops => l_max_iops,
13 max_mbps => l_max_mbps,
14 actual_latency => l_actual_latency
15 );
16
17 dbms_output.put_line ('max_iops = ' || l_max_iops);
18 dbms_output.put_line ('actual_latency = ' || l_actual_latency);
19 dbms_output.put_line('max_mbps = ' || l_max_mbps);
20
21 END;
22 /

max_iops = 11750
actual_latency = 0
max_mbps = 0

PL/SQL procedure successfully completed.

Elapsed: 00:53:20.45
SQL>
SQL>
SQL> select * from gv$io_calibration_status;

INST_ID STATUS CALIBRATION_TIME
---------- ------------- ---------------------------------------------------------------------------
1 READY 05-OCT-11 02.56.40.929 PM

Elapsed: 00:00:00.00
SQL>
SQL> set linesize 150
SQL> column start_time format a30
SQL> column end_time format a30
SQL> column num_physical_disks format 9999 heading NPD
SQL> select * from dba_rsrc_io_calibrate;

START_TIME END_TIME MAX_IOPS MAX_MBPS MAX_PMBPS LATENCY NPD
------------------------------ ------------------------------ ---------- ---------- ---------- ---------- -----
05-OCT-11 02.03.20.489842 PM 05-OCT-11 02.56.40.928773 PM 11750 0 186 0 30

Elapsed: 00:00:00.00


Kind regards,

Freek D'Hooge
Uptime
Oracle Database Administrator
email: [email protected]
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