PERF_OBJECT_TYPE

The PERF_OBJECT_TYPE structure describes object-specific performance information. This structure is followed by a list of PERF_COUNTER_DEFINITION structures, one for each counter defined for the type of object.

typedef struct _PERF_OBJECT_TYPE { 
  DWORD  TotalByteLength; 
  DWORD  DefinitionLength; 
  DWORD  HeaderLength; 
  DWORD  ObjectNameTitleIndex; 
  LPWSTR ObjectNameTitle; 
  DWORD  ObjectHelpTitleIndex; 
  LPWSTR ObjectHelpTitle; 
  DWORD  DetailLevel; 
  DWORD  NumCounters; 
  DWORD  DefaultCounter; 
  DWORD  NumInstances; 
  DWORD  CodePage; 
  LARGE_INTEGER PerfTime; 
  LARGE_INTEGER PerfFreq; 
} PERF_OBJECT_TYPE; 

Members

TotalByteLength

Contains the length, in bytes, of the object-specific data. This value includes this structure, the PERF_COUNTER_DEFINITION structures, and the PERF_INSTANCE_DEFINITION and PERF_COUNTER_BLOCK structures for each instance. This member specifies the offset from the beginning of this structure to the next PERF_OBJECT_TYPE structure if one exists.

DefinitionLength

Contains the length, in bytes, of the object-specific data. This value includes this structure and the PERF_COUNTER_DEFINITION structures for this object. This member is the offset from the beginning of the PERF_OBJECT_TYPE structure to the first PERF_INSTANCE_DEFINITION structure or to the PERF_COUNTER_DEFINITION structures if there is no instance data.

HeaderLength

Contains the length, in bytes, of this structure. This member is the offset to the first PERF_COUNTER_DEFINITION structure for this object.

ObjectNameTitleIndex

Contains the index to the object's name in the title database.

ObjectNameTitle

A pointer to a null-terminated string containing the name of the object. This member initially contains NULL, but it can contain a pointer to the actual string once the string is located.

ObjectHelpTitleIndex

Contains the index to the object's Help title in the title database.

ObjectHelpTitle

A pointer to a null-terminated string containing the title of Help. This member initially contains NULL, but it can contain a pointer to the actual string once the string is located.

DetailLevel

Specifies the level of detail. Applications use this value to control display complexity. This value is the minimum detail level of all the counters for a given object. This member can be one of the following values.

Detail level	Meaning
PERF_DETAIL_NOVICE	No technical ability is required to understand the counter data.
PERF_DETAIL_ADVANCED	The counter data is provided for advanced users.
PERF_DETAIL_EXPERT	The counter data is provided for expert users.
PERF_DETAIL_WIZARD	The counter data is provided for system designers.

NumCounters

Specifies the number of counters in each counter block. There is one counter block per instance.

DefaultCounter

Specifies the default counter whose information is to be displayed when this object is selected. This member is typically greater than or equal to zero. However, this member may be –1 to indicate that there is no default.

NumInstances

Specifies the number of object instances for which counters are being provided. If the object can have zero or more instances, but has none at present, this value should be zero. If the object cannot have multiple instances, this value should be PERF_NO_INSTANCES.

CodePage

Specifies the code page. This member is zero if the instance strings are in Unicode. Otherwise, this member is the code-page identifier of the instance names.

PerfTime

Specifies the current value, in counts, of the high-resolution performance counter.

PerfFreq

Specifies the current frequency, in counts per second, of the high-resolution performance counter.

Remarks

If there is only one instance of the object type, the counter definitions are followed by a single PERF_COUNTER_BLOCK structure. This structure is followed by data for each counter. (The PERF_COUNTER_BLOCK structure contains the total length of the structure and the counter data that follows it.)

If there is more than one instance of the object type, the list of counter definitions is followed by a PERF_INSTANCE_DEFINITION structure and a PERF_COUNTER_BLOCK structure for each instance. The PERF_INSTANCE_DEFINITION structure includes the name, the identifier, and the name of the parent of the instance.

Following the counter data, there is a PERF_INSTANCE_DEFINITION structure and a PERF_COUNTER_BLOCK structure for each instance specified in the PERF_DATA_BLOCK structure that begins the performance-data area.

Requirements

  Windows NT/2000: Requires Windows NT 3.1 or later.
  Header: Declared in Winperf.h; include Windows.h.

See Also

PERF_COUNTER_BLOCK, PERF_COUNTER_DEFINITION, PERF_INSTANCE_DEFINITION