Performance Counters
Overview of the Performance Counters technology.
To develop Performance Counters, you need these headers:
For programming guidance for this technology, see:
Enumerations
| PerfCounterDataType Indicates the content type of a PERF_COUNTER_HEADER block that the PerfQueryCounterData function includes as part of the PERF_DATA_HEADER block that the function produces as output. |
| PerfRegInfoType Indicates the types of information that you can request about a performance counter set by calling the PerfQueryCounterSetRegistrationInfo function. |
Functions
| CounterPathCallBack Applications implement the CounterPathCallBack function to process the counter path strings returned by the Browse dialog box. |
| LoadPerfCounterTextStringsA Loads onto the computer the performance objects and counters defined in the specified initialization file. (ANSI) |
| LoadPerfCounterTextStringsW Loads onto the computer the performance objects and counters defined in the specified initialization file. (Unicode) |
| PdhAddCounterA Adds the specified counter to the query. (ANSI) |
| PdhAddCounterW Adds the specified counter to the query. (Unicode) |
| PdhAddEnglishCounterA Adds the specified language-neutral counter to the query. (ANSI) |
| PdhAddEnglishCounterW Adds the specified language-neutral counter to the query. (Unicode) |
| PdhBindInputDataSourceA Binds one or more binary log files together for reading log data. (ANSI) |
| PdhBindInputDataSourceW Binds one or more binary log files together for reading log data. (Unicode) |
| PdhBrowseCountersA Displays a Browse Counters dialog box that the user can use to select one or more counters that they want to add to the query. To use handles to data sources, use the PdhBrowseCountersH function. (ANSI) |
| PdhBrowseCountersHA Displays a Browse Counters dialog box that the user can use to select one or more counters that they want to add to the query. This function is identical to the PdhBrowseCounters function, except that it supports the use of handles to data sources. (ANSI) |
| PdhBrowseCountersHW Displays a Browse Counters dialog box that the user can use to select one or more counters that they want to add to the query. This function is identical to the PdhBrowseCounters function, except that it supports the use of handles to data sources. (Unicode) |
| PdhBrowseCountersW Displays a Browse Counters dialog box that the user can use to select one or more counters that they want to add to the query. To use handles to data sources, use the PdhBrowseCountersH function. (Unicode) |
| PdhCalculateCounterFromRawValue Calculates the displayable value of two raw counter values. |
| PdhCloseLog Closes the specified log file. |
| PdhCloseQuery Closes all counters contained in the specified query, closes all handles related to the query, and frees all memory associated with the query. |
| PdhCollectQueryData Collects the current raw data value for all counters in the specified query and updates the status code of each counter. (PdhCollectQueryData) |
| PdhCollectQueryDataEx Uses a separate thread to collect the current raw data value for all counters in the specified query. The function then signals the application-defined event and waits the specified time interval before returning. |
| PdhCollectQueryDataWithTime Collects the current raw data value for all counters in the specified query and updates the status code of each counter. (PdhCollectQueryDataWithTime) |
| PdhComputeCounterStatistics Computes statistics for a counter from an array of raw values. |
| PdhConnectMachineA Connects to the specified computer. (ANSI) |
| PdhConnectMachineW Connects to the specified computer. (Unicode) |
| PdhEnumLogSetNamesA Enumerates the names of the log sets within the DSN. (ANSI) |
| PdhEnumLogSetNamesW Enumerates the names of the log sets within the DSN. (Unicode) |
| PdhEnumMachinesA Returns a list of the computer names associated with counters in a log file. (PdhEnumMachinesA) |
| PdhEnumMachinesHA Returns a list of the computer names associated with counters in a log file. (PdhEnumMachinesHA) |
| PdhEnumMachinesHW Returns a list of the computer names associated with counters in a log file. (PdhEnumMachinesHW) |
| PdhEnumMachinesW Returns a list of the computer names associated with counters in a log file. (PdhEnumMachinesW) |
| PdhEnumObjectItemsA Returns the specified object's counter and instance names that exist on the specified computer or in the specified log file. To use handles to data sources, use the PdhEnumObjectItemsH function. (ANSI) |
| PdhEnumObjectItemsHA Returns the specified object's counter and instance names that exist on the specified computer or in the specified log file. This function is identical to the PdhEnumObjectItems function, except that it supports the use of handles to data sources. (ANSI) |
| PdhEnumObjectItemsHW Returns the specified object's counter and instance names that exist on the specified computer or in the specified log file. This function is identical to the PdhEnumObjectItems function, except that it supports the use of handles to data sources. (Unicode) |
| PdhEnumObjectItemsW Returns the specified object's counter and instance names that exist on the specified computer or in the specified log file. To use handles to data sources, use the PdhEnumObjectItemsH function. (Unicode) |
| PdhEnumObjectsA Returns a list of objects available on the specified computer or in the specified log file. To use handles to data sources, use the PdhEnumObjectsH function. (ANSI) |
| PdhEnumObjectsHA Returns a list of objects available on the specified computer or in the specified log file.This function is identical to PdhEnumObjects, except that it supports the use of handles to data sources. (ANSI) |
| PdhEnumObjectsHW Returns a list of objects available on the specified computer or in the specified log file.This function is identical to PdhEnumObjects, except that it supports the use of handles to data sources. (Unicode) |
| PdhEnumObjectsW Returns a list of objects available on the specified computer or in the specified log file. To use handles to data sources, use the PdhEnumObjectsH function. (Unicode) |
| PdhExpandCounterPathA Examines the specified computer (or local computer if none is specified) for counters and instances of counters that match the wildcard strings in the counter path. (ANSI) |
| PdhExpandCounterPathW Examines the specified computer (or local computer if none is specified) for counters and instances of counters that match the wildcard strings in the counter path. (Unicode) |
| PdhExpandWildCardPathA Examines the specified computer or log file and returns those counter paths that match the given counter path which contains wildcard characters. To use handles to data sources, use the PdhExpandWildCardPathH function. (ANSI) |
| PdhExpandWildCardPathHA Examines the specified computer or log file and returns those counter paths that match the given counter path which contains wildcard characters.This function is identical to the PdhExpandWildCardPath function, except that it supports the use of handles to data sources. (ANSI) |
| PdhExpandWildCardPathHW Examines the specified computer or log file and returns those counter paths that match the given counter path which contains wildcard characters.This function is identical to the PdhExpandWildCardPath function, except that it supports the use of handles to data sources. (Unicode) |
| PdhExpandWildCardPathW Examines the specified computer or log file and returns those counter paths that match the given counter path which contains wildcard characters. To use handles to data sources, use the PdhExpandWildCardPathH function. (Unicode) |
| PdhFormatFromRawValue Computes a displayable value for the given raw counter values. |
| PdhGetCounterInfoA Retrieves information about a counter, such as data size, counter type, path, and user-supplied data values. (ANSI) |
| PdhGetCounterInfoW Retrieves information about a counter, such as data size, counter type, path, and user-supplied data values. (Unicode) |
| PdhGetCounterTimeBase Returns the time base of the specified counter. |
| PdhGetDataSourceTimeRangeA Determines the time range, number of entries and, if applicable, the size of the buffer containing the performance data from the specified input source. To use handles to data sources, use the PdhGetDataSourceTimeRangeH function. (ANSI) |
| PdhGetDataSourceTimeRangeH Determines the time range, number of entries and, if applicable, the size of the buffer containing the performance data from the specified input source.This function is identical to the PdhGetDataSourceTimeRange function, except that it supports the use of handles to data sources. |
| PdhGetDataSourceTimeRangeW Determines the time range, number of entries and, if applicable, the size of the buffer containing the performance data from the specified input source. To use handles to data sources, use the PdhGetDataSourceTimeRangeH function. (Unicode) |
| PdhGetDefaultPerfCounterA Retrieves the name of the default counter for the specified object. This name can be used to set the initial counter selection in the Browse Counter dialog box. To use handles to data sources, use the PdhGetDefaultPerfCounterH function. (ANSI) |
| PdhGetDefaultPerfCounterHA Retrieves the name of the default counter for the specified object. (ANSI) |
| PdhGetDefaultPerfCounterHW Retrieves the name of the default counter for the specified object. (Unicode) |
| PdhGetDefaultPerfCounterW Retrieves the name of the default counter for the specified object. This name can be used to set the initial counter selection in the Browse Counter dialog box. To use handles to data sources, use the PdhGetDefaultPerfCounterH function. (Unicode) |
| PdhGetDefaultPerfObjectA Retrieves the name of the default object. This name can be used to set the initial object selection in the Browse Counter dialog box. To use handles to data sources, use the PdhGetDefaultPerfObjectH function. (ANSI) |
| PdhGetDefaultPerfObjectHA Retrieves the name of the default object. (ANSI) |
| PdhGetDefaultPerfObjectHW Retrieves the name of the default object. (Unicode) |
| PdhGetDefaultPerfObjectW Retrieves the name of the default object. This name can be used to set the initial object selection in the Browse Counter dialog box. To use handles to data sources, use the PdhGetDefaultPerfObjectH function. (Unicode) |
| PdhGetDllVersion Returns the version of the currently installed Pdh.dll file. |
| PdhGetFormattedCounterArrayA Returns an array of formatted counter values. Use this function when you want to format the counter values of a counter that contains a wildcard character for the instance name. (ANSI) |
| PdhGetFormattedCounterArrayW Returns an array of formatted counter values. Use this function when you want to format the counter values of a counter that contains a wildcard character for the instance name. (Unicode) |
| PdhGetFormattedCounterValue Computes a displayable value for the specified counter. |
| PdhGetLogFileSize Returns the size of the specified log file. |
| PdhGetRawCounterArrayA Returns an array of raw values from the specified counter. Use this function when you want to retrieve the raw counter values of a counter that contains a wildcard character for the instance name. (ANSI) |
| PdhGetRawCounterArrayW Returns an array of raw values from the specified counter. Use this function when you want to retrieve the raw counter values of a counter that contains a wildcard character for the instance name. (Unicode) |
| PdhGetRawCounterValue Returns the current raw value of the counter. |
| PdhIsRealTimeQuery Determines if the specified query is a real-time query. |
| PdhLookupPerfIndexByNameA Returns the counter index corresponding to the specified counter name. (ANSI) |
| PdhLookupPerfIndexByNameW Returns the counter index corresponding to the specified counter name. (Unicode) |
| PdhLookupPerfNameByIndexA Returns the performance object name or counter name corresponding to the specified index. (ANSI) |
| PdhLookupPerfNameByIndexW Returns the performance object name or counter name corresponding to the specified index. (Unicode) |
| PdhMakeCounterPathA Creates a full counter path using the members specified in the PDH_COUNTER_PATH_ELEMENTS structure. (ANSI) |
| PdhMakeCounterPathW Creates a full counter path using the members specified in the PDH_COUNTER_PATH_ELEMENTS structure. (Unicode) |
| PdhOpenLogA Opens the specified log file for reading or writing. (ANSI) |
| PdhOpenLogW Opens the specified log file for reading or writing. (Unicode) |
| PdhOpenQueryA Creates a new query that is used to manage the collection of performance data. To use handles to data sources, use the PdhOpenQueryH function. (ANSI) |
| PdhOpenQueryH Creates a new query that is used to manage the collection of performance data. This function is identical to the PdhOpenQuery function, except that it supports the use of handles to data sources. |
| PdhOpenQueryW Creates a new query that is used to manage the collection of performance data. To use handles to data sources, use the PdhOpenQueryH function. (Unicode) |
| PdhParseCounterPathA Parses the elements of the counter path and stores the results in the PDH_COUNTER_PATH_ELEMENTS structure. (ANSI) |
| PdhParseCounterPathW Parses the elements of the counter path and stores the results in the PDH_COUNTER_PATH_ELEMENTS structure. (Unicode) |
| PdhParseInstanceNameA Parses the elements of an instance string. (ANSI) |
| PdhParseInstanceNameW Parses the elements of an instance string. (Unicode) |
| PdhReadRawLogRecord Reads the information in the specified binary trace log file. |
| PdhRemoveCounter Removes a counter from a query. |
| PdhSelectDataSourceA Displays a dialog window that prompts the user to specify the source of the performance data. (ANSI) |
| PdhSelectDataSourceW Displays a dialog window that prompts the user to specify the source of the performance data. (Unicode) |
| PdhSetCounterScaleFactor Sets the scale factor that is applied to the calculated value of the specified counter when you request the formatted counter value. If the PDH_FMT_NOSCALE flag is set, then this scale factor is ignored. |
| PdhSetDefaultRealTimeDataSource Specifies the source of the real-time data. |
| PdhSetQueryTimeRange Limits the samples that you can read from a log file to those within the specified time range, inclusively. |
| PdhUpdateLogA Collects counter data for the current query and writes the data to the log file. (ANSI) |
| PdhUpdateLogFileCatalog Synchronizes the information in the log file catalog with the performance data in the log file. |
| PdhUpdateLogW Collects counter data for the current query and writes the data to the log file. (Unicode) |
| PdhValidatePathA Validates that the counter is present on the computer specified in the counter path. (ANSI) |
| PdhValidatePathExA Validates that the specified counter is present on the computer or in the log file. (ANSI) |
| PdhValidatePathExW Validates that the specified counter is present on the computer or in the log file. (Unicode) |
| PdhValidatePathW Validates that the counter is present on the computer specified in the counter path. (Unicode) |
| PERF_MEM_ALLOC Providers implement this function to provide custom memory management for PERFLIB.A |
| PERF_MEM_FREE Providers implement this function to provide custom memory management for PERFLIB.F |
| PerfAddCounters Adds performance counter specifications to the specified query. |
| PerfCloseQueryHandle Closes a query handle that you opened by calling PerfOpenQueryHandle. |
| PerfCreateInstance Creates an instance of the specified counter set. |
| PerfDecrementULongCounterValue Decrements the value of a counter whose value is a 4-byte unsigned integer. Providers use this function. |
| PerfDecrementULongLongCounterValue Decrements the value of a counter whose value is an 8-byte unsigned integer. Providers use this function. |
| PerfDeleteCounters Removes the specified performance counter specifications from the specified query. |
| PerfDeleteInstance Deletes an instance of the counter set created by the PerfCreateInstance function. |
| PerfEnumerateCounterSet Gets the counter set identifiers of the counter sets that are registered on the specified system. Counter set identifiers are globally unique identifiers (GUIDs). |
| PerfEnumerateCounterSetInstances Gets the names and identifiers of the active instances of a counter set on the specified system. |
| PerfIncrementULongCounterValue Increments the value of a counter whose value is a 4-byte unsigned integer. Providers use this function. |
| PerfIncrementULongLongCounterValue Increments the value of a counter whose value is an 8-byte unsigned integer. Providers use this function. |
| PERFLIBREQUEST Providers can implement this function to receive notification when consumers perform certain actions, such as adding or removing counters from a query. |
| PerfOpenQueryHandle Creates a handle that references a query on the specified system. A query is a list of counter specifications. |
| PerfQueryCounterData Gets the values of the performance counters that match the counter specifications in the specified query. |
| PerfQueryCounterInfo Gets the counter specifications in the specified query. |
| PerfQueryCounterSetRegistrationInfo Gets information about a counter set on the specified system. |
| PerfQueryInstance Retrieves a pointer to the specified counter set instance. Providers use this function. |
| PerfSetCounterRefValue Updates the value of a counter whose value is a pointer to the actual data. Providers use this function. |
| PerfSetCounterSetInfo Specifies the layout of a particular counter set. |
| PerfSetULongCounterValue Updates the value of a counter whose value is a 4-byte unsigned integer. Providers use this function. |
| PerfSetULongLongCounterValue Updates the value of a counter whose value is an 8-byte unsigned integer. Providers use this function. |
| PerfStartProvider Registers the provider. (PerfStartProvider) |
| PerfStartProviderEx Registers the provider. (PerfStartProviderEx) |
| PerfStopProvider Removes the provider's registration from the list of registered providers and frees all resources associated with the provider. |
| PM_CLOSE_PROC Performs the cleanup required by your performance DLL. |
| PM_COLLECT_PROC Collects the performance data and returns it to the consumer. |
| UnloadPerfCounterTextStringsA Unloads performance objects and counters from the computer for the specified application. (ANSI) |
| UnloadPerfCounterTextStringsW Unloads performance objects and counters from the computer for the specified application. (Unicode) |
Structures
| PDH_BROWSE_DLG_CONFIG_A The PDH_BROWSE_DLG_CONFIG structure is used by the PdhBrowseCounters function to configure the Browse Performance Counters dialog box. (ANSI) |
| PDH_BROWSE_DLG_CONFIG_HA The PDH_BROWSE_DLG_CONFIG_H structure is used by the PdhBrowseCountersH function to configure the Browse Performance Counters dialog box. (ANSI) |
| PDH_BROWSE_DLG_CONFIG_HW The PDH_BROWSE_DLG_CONFIG_H structure is used by the PdhBrowseCountersH function to configure the Browse Performance Counters dialog box. (Unicode) |
| PDH_BROWSE_DLG_CONFIG_W The PDH_BROWSE_DLG_CONFIG structure is used by the PdhBrowseCounters function to configure the Browse Performance Counters dialog box. (Unicode) |
| PDH_COUNTER_INFO_A The PDH_COUNTER_INFO structure contains information describing the properties of a counter. This information also includes the counter path. (ANSI) |
| PDH_COUNTER_INFO_W The PDH_COUNTER_INFO structure contains information describing the properties of a counter. This information also includes the counter path. (Unicode) |
| PDH_COUNTER_PATH_ELEMENTS_A The PDH_COUNTER_PATH_ELEMENTS structure contains the components of a counter path. (ANSI) |
| PDH_COUNTER_PATH_ELEMENTS_W The PDH_COUNTER_PATH_ELEMENTS structure contains the components of a counter path. (Unicode) |
| PDH_DATA_ITEM_PATH_ELEMENTS_A The PDH_DATA_ITEM_PATH_ELEMENTS structure contains the path elements of a specific data item. (ANSI) |
| PDH_DATA_ITEM_PATH_ELEMENTS_W The PDH_DATA_ITEM_PATH_ELEMENTS structure contains the path elements of a specific data item. (Unicode) |
| PDH_FMT_COUNTERVALUE The PDH_FMT_COUNTERVALUE structure contains the computed value of the counter and its status. |
| PDH_FMT_COUNTERVALUE_ITEM_A The PDH_FMT_COUNTERVALUE_ITEM structure contains the instance name and formatted value of a counter. (ANSI) |
| PDH_FMT_COUNTERVALUE_ITEM_W The PDH_FMT_COUNTERVALUE_ITEM structure contains the instance name and formatted value of a counter. (Unicode) |
| PDH_RAW_COUNTER The PDH_RAW_COUNTER structure returns the data as it was collected from the counter provider. No translation, formatting, or other interpretation is performed on the data. |
| PDH_RAW_COUNTER_ITEM_A The PDH_RAW_COUNTER_ITEM structure contains the instance name and raw value of a counter. (ANSI) |
| PDH_RAW_COUNTER_ITEM_W The PDH_RAW_COUNTER_ITEM structure contains the instance name and raw value of a counter. (Unicode) |
| PDH_RAW_LOG_RECORD The PDH_RAW_LOG_RECORD structure contains information about a binary trace log file record. |
| PDH_STATISTICS The PDH_STATISTICS structure contains the minimum, maximum, and mean values for an array of raw counters values. |
| PDH_TIME_INFO The PDH_TIME_INFO structure contains information on time intervals as applied to the sampling of performance data. |
| PERF_COUNTER_BLOCK Describes the block of memory that contains the raw performance counter data for an object's counters. |
| PERF_COUNTER_DATA Contains information about the PERF_COUNTER_DATA block that contains the structure. |
| PERF_COUNTER_DEFINITION Describes a performance counter. |
| PERF_COUNTER_HEADER Contains information about the PERF_COUNTER_HEADER block that contains the structure. |
| PERF_COUNTER_IDENTIFIER Contains information about the PERF_COUNTER_IDENTIFIER block that contains the structure. |
| PERF_COUNTER_IDENTITY Defines the counter that is sent to a provider's callback when the consumer adds or removes a counter from the query. |
| PERF_COUNTER_INFO Defines information about a counter that a provider uses. The CTRPP tool automatically generates this structure based on the schema you specify. |
| PERF_COUNTER_REG_INFO Provides registration information about a performance counter. |
| PERF_COUNTERSET_INFO Defines information about a counter set that a provider uses. The CTRPP tool automatically generates this structure based on the schema you specify. |
| PERF_COUNTERSET_INSTANCE Defines an instance of a counter set. |
| PERF_COUNTERSET_REG_INFO Contains information about the PERF_COUNTERSET_REG_INFO block that contains the structure. |
| PERF_DATA_BLOCK Describes the performance data block that you queried, for example, the number of performance objects returned by the provider and the time-based values that you use when calculating performance values. |
| PERF_DATA_HEADER Provides information about the PERF_DATA_HEADER block that contains the structure. |
| PERF_INSTANCE_DEFINITION Describes an instance of a performance object. |
| PERF_INSTANCE_HEADER Provides information about the PERF_INSTANCE_HEADER block that contains the structure. |
| PERF_MULTI_COUNTERS Provides information about the PERF_MULTI_COUNTERS block that contains the structure. |
| PERF_MULTI_INSTANCES Provides information about the PERF_MULTI_INSTANCES block that contains the structure. |
| PERF_OBJECT_TYPE Describes object-specific performance information, for example, the number of instances of the object and the number of counters that the object defines. |
| PERF_PROVIDER_CONTEXT Defines provider context information. |
| PERF_STRING_BUFFER_HEADER Provides information about the PERF_STRING_BUFFER_HEADER block that contains the structure. |
| PERF_STRING_COUNTER_HEADER Indicates where in the PERF_STRING_BUFFER_HEADER block that the string that contains the name or help string for the indicated performance counter starts. |
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