线程优先级

通过SetThreadPriority可以设置线程优先级别：

WINBASEAPI
BOOL
WINAPI
SetThreadPriority(
　　_In_ HANDLE hThread,     //线程句柄
　　_In_ int nPriority                   //设置的权限级别
); 

MSDN：

Priority	Meaning
THREAD_MODE_BACKGROUND_BEGIN 0x00010000	Begin background processing mode. The system lowers the resource scheduling priorities of the thread so that it can perform background work without significantly affecting activity in the foreground. This value can be specified only if hThread is a handle to the current thread. The function fails if the thread is already in background processing mode. Windows Server 2003:This value is not supported.
THREAD_MODE_BACKGROUND_END 0x00020000	End background processing mode. The system restores the resource scheduling priorities of the thread as they were before the thread entered background processing mode. This value can be specified only if hThread is a handle to the current thread. The function fails if the thread is not in background processing mode. Windows Server 2003:This value is not supported.
THREAD_PRIORITY_ABOVE_NORMAL 1	Priority 1 point above the priority class.
THREAD_PRIORITY_BELOW_NORMAL -1	Priority 1 point below the priority class.
THREAD_PRIORITY_HIGHEST 2	Priority 2 points above the priority class.
THREAD_PRIORITY_IDLE -15	Base priority of 1 for IDLE_PRIORITY_CLASS, BELOW_NORMAL_PRIORITY_CLASS, NORMAL_PRIORITY_CLASS, ABOVE_NORMAL_PRIORITY_CLASS, or HIGH_PRIORITY_CLASS processes, and a base priority of 16 for REALTIME_PRIORITY_CLASS processes.
THREAD_PRIORITY_LOWEST -2	Priority 2 points below the priority class.
THREAD_PRIORITY_NORMAL 0	Normal priority for the priority class.
THREAD_PRIORITY_TIME_CRITICAL 15	Base priority of 15 for IDLE_PRIORITY_CLASS, BELOW_NORMAL_PRIORITY_CLASS, NORMAL_PRIORITY_CLASS, ABOVE_NORMAL_PRIORITY_CLASS, or HIGH_PRIORITY_CLASS processes, and a base priority of 31 for REALTIME_PRIORITY_CLASS processes.

// 线程优先级.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include <Windows.h>  
DWORD WINAPI ThreadProcIdle(LPVOID lpParameter);
DWORD WINAPI ThreadProcNormal(LPVOID lpParameter);


int main()
{
	DWORD ThreadPriority_Idle;
	DWORD ThreadIdPriority_CriticalTime;
	HANDLE ThreadHandle[2];

	ThreadHandle[0] = CreateThread(NULL, 0, ThreadProcIdle, NULL, CREATE_SUSPENDED, &ThreadPriority_Idle);
	SetThreadPriority(ThreadHandle[0], THREAD_PRIORITY_IDLE);
	ResumeThread(ThreadHandle[0]);
	
	ThreadHandle[1] = CreateThread(NULL, 0, ThreadProcNormal, NULL, CREATE_SUSPENDED, &ThreadIdPriority_CriticalTime);
	//更多的CPU占有时间
	SetThreadPriority(ThreadHandle[1], THREAD_PRIORITY_TIME_CRITICAL);
	ResumeThread(ThreadHandle[1]);


	WaitForMultipleObjects(2, ThreadHandle, TRUE, INFINITE);
	CloseHandle(ThreadHandle[0]);
	CloseHandle(ThreadHandle[1]);
	return 0;
}

DWORD WINAPI ThreadProcIdle(LPVOID lpParameter)
{
	for (int i = 0; i<200; i++)
	{
		printf("I'm THREAD_PRIORITY_IDLE...
");
	}
	return 0;
}

DWORD WINAPI ThreadProcNormal(LPVOID lpParameter)
{
	for (int i = 0; i<200; i++)
	{
		printf("I'm THREAD_MODE_BACKGROUND_END ...
");
	}
	return 0;
}