计数Windows中特定进程的上下文切换

这里有一种方法 – 这将打印记事本的线程0使用的上下文切换的数量（您可以在CounterPathBuffer初始化中替换您想要的任何进程和线程数）每秒：

#include "stdafx.h" #include <iostream> #include <windows.h> #include <stdio.h> #include <conio.h> #include <pdh.h> #include <pdhmsg.h> #pragma comment(lib, "pdh.lib") using namespace std; CONST ULONG SAMPLE_INTERVAL_MS = 1000; CONST PWSTR BROWSE_DIALOG_CAPTION = L"Select a counter to monitor."; void wmain(void) { PDH_STATUS Status; HQUERY Query = NULL; HCOUNTER Counter; PDH_FMT_COUNTERVALUE DisplayValue; DWORD CounterType; SYSTEMTIME SampleTime; PDH_BROWSE_DLG_CONFIG BrowseDlgData; WCHAR CounterPathBuffer[PDH_MAX_COUNTER_PATH] = L"\\\\ComputerNameGoesHere\\Thread(notepad/0)\\Context Switches/sec"; // // Create a query. // Status = PdhOpenQuery(NULL, NULL, &Query); if (Status != ERROR_SUCCESS) { wprintf(L"\nPdhOpenQuery failed with status 0x%x.", Status); goto Cleanup; } // // Initialize the browser dialog window settings. // ZeroMemory(&BrowseDlgData, sizeof(PDH_BROWSE_DLG_CONFIG)); BrowseDlgData.bIncludeInstanceIndex = FALSE; BrowseDlgData.bSingleCounterPerAdd = TRUE; BrowseDlgData.bSingleCounterPerDialog = TRUE; BrowseDlgData.bLocalCountersOnly = FALSE; BrowseDlgData.bWildCardInstances = TRUE; BrowseDlgData.bHideDetailBox = TRUE; BrowseDlgData.bInitializePath = FALSE; BrowseDlgData.bDisableMachineSelection = FALSE; BrowseDlgData.bIncludeCostlyObjects = FALSE; BrowseDlgData.bShowObjectBrowser = FALSE; BrowseDlgData.hWndOwner = NULL; BrowseDlgData.szReturnPathBuffer = CounterPathBuffer; BrowseDlgData.cchReturnPathLength = PDH_MAX_COUNTER_PATH; BrowseDlgData.pCallBack = NULL; BrowseDlgData.dwCallBackArg = 0; BrowseDlgData.CallBackStatus = ERROR_SUCCESS; BrowseDlgData.dwDefaultDetailLevel = PERF_DETAIL_WIZARD; BrowseDlgData.szDialogBoxCaption = BROWSE_DIALOG_CAPTION; // // Add the selected counter to the query. // Status = PdhAddCounter(Query, CounterPathBuffer, 0, &Counter); if (Status != ERROR_SUCCESS) { wprintf(L"\nPdhAddCounter failed with status 0x%x.", Status); goto Cleanup; } // // Most counters require two sample values to display a formatted value. // PDH stores the current sample value and the previously collected // sample value. This call retrieves the first value that will be used // by PdhGetFormattedCounterValue in the first iteration of the loop // Note that this value is lost if the counter does not require two // values to compute a displayable value. // Status = PdhCollectQueryData(Query); if (Status != ERROR_SUCCESS) { wprintf(L"\nPdhCollectQueryData failed with 0x%x.\n", Status); goto Cleanup; } // // Print counter values until a key is pressed. // while (!_kbhit()) { Sleep(SAMPLE_INTERVAL_MS); GetLocalTime(&SampleTime); Status = PdhCollectQueryData(Query); if (Status != ERROR_SUCCESS) { wprintf(L"\nPdhCollectQueryData failed with status 0x%x.", Status); } wprintf(L"\n\"%2.2d/%2.2d/%4.4d %2.2d:%2.2d:%2.2d.%3.3d\"", SampleTime.wMonth, SampleTime.wDay, SampleTime.wYear, SampleTime.wHour, SampleTime.wMinute, SampleTime.wSecond, SampleTime.wMilliseconds); // // Compute a displayable value for the counter. // Status = PdhGetFormattedCounterValue(Counter, PDH_FMT_DOUBLE, &CounterType, &DisplayValue); if (Status != ERROR_SUCCESS) { wprintf(L"\nPdhGetFormattedCounterValue failed with status 0x%x.", Status); goto Cleanup; } wprintf(L",\"%.20g\"", DisplayValue.doubleValue); } Cleanup: // // Close the query. // if (Query) { PdhCloseQuery(Query); } int x; cin >>x; } 

大部分的代码是从这个来源： msdn.microsoft.com/en-us/library/aa371886%28v=vs.85%29.aspx 。 我想缩短上下文切换连续检查之间的时间（使其小于一秒）。 如果任何人有任何想法如何做到这一点，这将是伟大的。

在互联网上搜索一下，我发现了一个名为“ 性能计数器 ”的东西，你可以提供计数器数据或者消耗计数器数据。 在你的情况下，我相信你想从性能计数器读取数据。

您可以使用注册表接口或PDH接口来使用性能数据。 PDH界面比注册表界面更易于使用，建议用于大多数性能数据收集任务。 PDH接口本质上是注册表接口提供的功能的更高级抽象。

这是另一篇来自Microsoft的关于Monitoring Context Switches的文章 。

如果需要，ETW（Windows事件跟踪）将为您提供有关上下文切换的更深层次的信息。 代码可能比访问性能计数器复杂得多。

初始链接： Windows 7中的核心操作系统事件和Windows性能工具包技术参考

搜索术语：“ETW上下文切换”，“xperf”