PERF_COUNTER_DEFINITION
The PERF_COUNTER_DEFINITION
structure describes a performance counter. The Unicode names in this structure
must appear in a message file.
typedef struct _PERF_COUNTER_DEFINITION { // pcd
DWORD ByteLength;
DWORD CounterNameTitleIndex;
LPWSTR
CounterNameTitle;
DWORD CounterHelpTitleIndex;
LPWSTR
CounterHelpTitle;
DWORD DefaultScale;
DWORD DetailLevel;
DWORD CounterType;
DWORD CounterSize;
DWORD CounterOffset;
} PERF_COUNTER_DEFINITION;
Members
ByteLength
Contains the
length, in bytes, of this structure.
CounterNameTitleIndex
Contains the
index of the counter name in the title database of the registry.
CounterNameTitle
Points to the
name of the counter. This member contains NULL, initially, but it can contain a
pointer to the actual string once the string is located.
CounterHelpTitleIndex
Contains the
index to the counter s Help title in the title database of the registry.
CounterHelpTitle
Points to the
title of Help. This member contains NULL, initially, but it can contain a
pointer to the actual string once the string is located.
DefaultScale
Specifies the
power of 10 by which to scale a chart line, assuming the vertical axis is 100.
If this value is zero, the scale value is 1; if this value is 1, the scale
value is 10; if this value is -1,
the scale value is .10; and so on.
DetailLevel
Specifies the
level of detail for the counter. Applications use this value to control display
complexity. This member can be one of the following values:
|
Value |
Meaning |
|
PERF_DETAIL_NOVICE |
The data
can be understood by the uninformed user. |
|
PERF_DETAIL_ADVANCED |
The data is
designed for the advanced user. |
|
PERF_DETAIL_EXPERT |
The data is
designed for the expert user. |
|
PERF_DETAIL_WIZARD |
The data is
designed for the system designer. |
CounterType
Specifies the
type of counter. This member is some combination of the following values.
These values indicate the counter s data size:
|
Value |
Meaning |
|
PERF_SIZE_DWORD |
The counter
data is a doubleword. |
|
PERF_SIZE_LARGE |
The counter
data is a large integer. |
|
PERF_SIZE_ZERO |
The counter
data is a zero-length field. |
|
PERF_SIZE_VARIABLE_LEN |
The size of
the counter data is in the CounterSize member. |
These values
indicate the additional contents of this member:
|
Value |
Meaning |
|
PERF_TYPE_NUMBER |
The counter
data is a number value but not a counter. |
|
PERF_TYPE_COUNTER |
The counter
data is an increasing numeric value. |
|
PERF_TYPE_TEXT |
The counter
data is a text field. |
|
PERF_TYPE_ZERO |
The counter
data is always zero. |
If
PERF_TYPE_NUMBER is specified, one of these values is also specified to
indicate the format of the number:
|
Value |
Meaning |
|
PERF_NUMBER_HEX |
The counter
data should be displayed as a hexadecimal value. |
|
PERF_NUMBER_DECIMAL |
The counter
data should be displayed as a decimal value. |
|
PERF_NUMBER_DEC_1000 |
The counter
data should be divided by 1000 and displayed as a decimal value. |
If
PERF_TYPE_COUNTER is specified, one of these values is also specified to
indicate the type of counter:
|
Value |
Meaning |
|
PERF_COUNTER_VALUE |
The counter
value is valid without additional calculation; that is, it should be
displayed as is. |
|
PERF_COUNTER_RATE |
The counter
value should be divided by the elapsed time. |
|
PERF_COUNTER_FRACTION |
The counter
value should be divided by the base value indicated by the next counter if it
is of type PERF_COUNTER_BASE or by the value of the counter subtype. |
|
PERF_COUNTER_BASE |
The counter
value is the base value to use in fractions. |
|
PERF_COUNTER_ELAPSED |
The counter
value is a start time to be subtracted from the current time. |
|
PERF_COUNTER_QUEUELEN |
The
performance application should use the Queuelen counter that is, the Queue Length Space-Time Product
formula. The next counter is the number currently in the queue. Multiply it
by the current time (units specified by this counter s subtype). Add the
product to the original value of the counter. To obtain the average queue
length, divide the result of the addition by the delta time. |
|
PERF_COUNTER_HISTOGRAM |
The counter
value begins or ends a histogram. |
If
PERF_TYPE_COUNTER is specified, one of these values is also specified to
indicate the subtype of counter:
|
Value |
Meaning |
|
PERF_TIMER_TICK |
The
frequency of the high-resolution performance counter should be used as the
base. |
|
PERF_TIMER_100NS |
The time
base units of the 100-nanosecond timer should be used as the base. |
|
PERF_OBJECT_TIMER |
The
object-timer frequency should be used as the base unit. This value is
system-defined in this counter s PERF_OBJECT_TYPE definition. |
If
PERF_TYPE_TEXT is specified, one of these values is also specified to indicate
the type of text:
|
Value |
Meaning |
|
PERF_TEXT_UNICODE |
The counter
data contains Unicode text. |
|
PERF_TEXT_ASCII |
The counter
data contains ASCII text. |
These values
indicate how to use the counter data in a calculation:
|
Value |
Meaning |
|
PERF_DELTA_COUNTER |
The
difference between the previous counter value and the current counter value
is computed before proceeding. |
|
PERF_DELTA_BASE |
The
difference between the previous base value and the current base value is
computed before proceeding. |
|
PERF_INVERSE_COUNTER |
After other
calculations, the counter should be inverted before displaying or converting
to a percentage. |
|
PERF_MULTI_COUNTER |
This value
is a sum of counters from several sources, the number of which is indicated
by the next counter. |
These values
indicate the display suffix of the counter data:
|
Value |
Meaning |
|
PERF_DISPLAY_NO_SUFFIX |
There is no
display suffix. |
|
PERF_DISPLAY_PER_SEC |
The display
suffix is /sec . |
|
PERF_DISPLAY_PERCENT |
The display
suffix is % . |
|
PERF_DISPLAY_SECONDS |
The display
suffix is secs . |
|
PERF_DISPLAY_NOSHOW |
The counter
value should not be displayed. |
CounterSize
Specifies the
counter size, in bytes.
CounterOffset
Specifies the
offset from the start of the PERF_COUNTER_BLOCK structure to the first byte
of this counter.
Remarks
This
structure is part of the performance data provided by the RegQueryValueEx
function when the HKEY_PERFORMANCE_DATA key is used.
See Also