Implementation details

This section explains implementation details under the following headings:

• Component provider implementation details

• Event generator implementation details

• Indication consumer implementation details

Component provider implementation details

1. Calls to instrumentation entry points operate within the context of the DMI-SP.

2. Before the component instrumentation uses the DmiRegisterCi(3dmi) function to register as direct instrumentation with the Service Provider, it must allocate a DmiAccessDataList_t data structure of the appropriate size. If you specify a size larger than the number of groups to be instrumented, the behavior is undefined.

   The size member of this data structure corresponds directly to the number of DmiAccessData structures used to describe the attributes that are to be registered for direct instrumentation. For example:

   • If all of the attributes within a particular ``component'' are instrumented, the value of both the GroupID and the AttributeID is 0. Only one DmiAccessData structure is used to describe the entire DmiAccessDataList_t structure.

   • If all the attributes within a particular ``group'' are instrumented, the value of the GroupID specifies the group and the AttributeID is 0. Only one DmiAccessData structure is used to describe the entire group. This becomes one member of the DmiAccessDataList_t structure.

     ---

     NOTE: If there are more groups to be defined, the component instrumentation will need to increase the size of the DmiAccessDataList_t structure.

     ---

   • If only some of the attributes within a particular group are instrumented, the value of the GroupID specifies the group, and the AttributeID specifies one of the instrumented attributes. This defines one DmiAccessData structure. There will be one DmiAccessData structure for each instrumented attribute within that group. If three attributes are defined within the specified group, there will be three DmiAccessData structures added to the members of the DmiAccessDataList_t structure.

Event generator implementation details

When allocating memory for the DmiMultiRowData_t structure for indications, the event generators must make sure that they allocate the correct amount of memory for the Standard Event Generation Group and for the group which generates indications.

For example, the first DmiRowData_t structure in the DmiMultiRowData_t array, the array that is required for event indications, should have space for seven attributes for the Event Generation Group. The second DmiRowData_t structure in the DmiMultiRowData_t array may allocate space for the number of attributes contained in the group which generates indications.

Indication consumer implementation details

For proper delivery of indication data to multiple management applications on multiple systems, the management applications should use the DmiGetSubscriptionAddress(3dmi) function during indication subscription. Otherwise, the Service Provider delivers indications only to management applications that are local to the system. For an example of using the DmiGetSubscriptionAddress(3dmi) function, refer to the indcons example in ``DMI 2.0 code samples''.