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11G

Resource Manager Enhancements

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Resource Manager Enhancements

 

ARTICLE YET TO BE REVIEWED AND IMPROVED

Prior to 11g consumers were mapped with consumer goups and the main resource plan directive was CPU. According to the consumer group a given session was mapped CPU resources were granted or not.

New in 11G is that the DBA has the choice between CPU based or IO based resource plan directives. A prerequisite is that async IO is enabled. The instance initialization parameter filesystemio_options needs to be set to SETALL or ASYNC

Resource plan directives can be IO constrained. ( see dbms_resource_manager package )

 

PLATINUM_SYS >show parameter filesystem


NAME                     TYPE     VALUE


filesystemio_options             string     SETALL

 

Initially the DBA needs to run the dbms_resource_manager.calibrate_io procedure to capture io throughput info from the IO subsystem

 

PLATINUM_SYS >declare

2  max_iopersec pls_integer;
3  max_mbpersec pls_integer;
4  latency      pls_integer;
5  begin
6  dbms_resource_manager.calibrate_io(
7  num_physical_disks=>1,
8  max_latency       =>20,
9  max_iops          =>max_iopersec,
10  max_mbps          =>max_mbpersec,
11  actual_latency    =>latency);
12  dbms_output.put_line('max io per sec ='

max_iopersec);
13  dbms_output.put_line('max Mb per sec ='
max_mbpersec);
14  dbms_output.put_line('latency        ='|| latency);
15  end;
16  /
max io per sec =98

max Mb per sec =35
latency        =19



PL/SQL procedure successfully completed.

 

Note there are several built in resource plans available in 11G, they can easily be activated using the GUI