Windows 10上的Java Thread.sleep()在S3睡眠状态下停止

2019年8月5日 111次阅读

有一个桌面应用程序使用Thread.sleep()来实现长(几分钟或几小时)延迟.这个应用程序从
Windows XP到(至少)Windows 7都运行良好.应用程序计算未来需要做多少事情,然后点击Thread.sleep(msToWait).即使系统在等待期间恰好进入S3睡眠状态,这一直工作正常.

但是,从Windows 10开始,如果机器已经在S3中,则Thread.sleep()之后的代码不会“按时”执行.似乎机器开始执行代码“msToWait”加上机器进入S3的时间(现在不是100％肯定,但很可能).

早期版本的Windows没有表现出这种行为; Thread.sleep()之后的代码等待了适当的时间,而不管睡眠状态如何.

测试已在当前的JVM 1.7上进行.

这是Windows 10的错误吗？这是一个JVM错误吗？有解决方法吗？

附加数据：

开发了测试程序和程序.程序是运行程序,使机器休眠约一分钟,然后唤醒机器并等待程序完成.

如果这个程序在JVM版本：25.40-b25的Windows 10(报告为8)上运行,则会失败：

C:\Users\Tester\Downloads>SleepTester.exe
Wed Apr 01 10:47:35 PDT 2015 Using default number of minutes: 5
Wed Apr 01 10:47:35 PDT 2015 You can use "SleepTester -minutes 10" to have it sleep for 10 minutes, for example.
Wed Apr 01 10:47:35 PDT 2015 JVM Version: 25.40-b25 Windows Version: Windows 8
Wed Apr 01 10:47:35 PDT 2015 The program will now wait for 5 minutes.  Expect wrap-up at Wed Apr 01 10:52:35 PDT 2015
Wed Apr 01 10:53:38 PDT 2015 The system has come through the Thread.sleep(300000).
Wed Apr 01 10:53:38 PDT 2015 This should be a low number: 63589
Wed Apr 01 10:53:38 PDT 2015 This appears to be operating incorrectly...the expected sleep time has NOT been achieved.
Wed Apr 01 10:53:38 PDT 2015 Program is ending.

如果该进程在Windows 7上运行,则不会失败.

Wed Apr 01 17:12:18 EDT 2015 Java Runtime Version: 1.8.0_31-b13 JVM Version: 25.31-b07 Windows Version: Windows 7
Wed Apr 01 17:12:18 EDT 2015 The program will now wait for 6 minutes.  Expect wrap-up at Wed Apr 01 17:18:18 EDT 2015
Wed Apr 01 17:18:18 EDT 2015 The system has come through the Thread.sleep(360000). 
Wed Apr 01 17:18:18 EDT 2015 This should be a low number: 0
Wed Apr 01 17:18:18 EDT 2015 Program is ending.

这是测试程序：

import java.util.Date;

public class SleepTester {

private static int mMinutes;
private static int mDefault = 5;

public static void main(String[] args) throws Exception {
    for (int iArg = 0; iArg < args.length; ++iArg) {
        if (args[iArg].equals("-minutes") && (iArg + 1) < args.length) {
            mMinutes = Integer.parseInt(args[++iArg]);
        }
    }

    if (mMinutes == 0) {
        mMinutes = mDefault;
        System.out.println(new Date() + " Using default number of minutes: " + mDefault);
        System.out.println(new Date() + " You can use \"SleepTester -minutes 10\" to have it sleep for 10 minutes, for example.");
    }

    System.out.println(new Date() + " Java Runtime Version: " + System.getProperty("java.runtime.version") + " JVM Version: " + System.getProperty("java.vm.version") + " Windows Version: " + System.getProperty("os.name"));
    long msDelay = mMinutes * 60 * 1000;
    long wakePoint = new Date().getTime() + msDelay;
    System.out.println(new Date() + " The program will now wait for " + mMinutes + " minutes.  Expect wrap-up at " + new Date(wakePoint));
    Thread.sleep(msDelay); // If the machine goes into S3 during this interval, it should not matter, as long as it's awake when it fires.
    System.out.println(new Date() + " The system has come through the Thread.sleep(" + msDelay + "). ");
    long msAccuracy = Math.abs(new Date().getTime() - wakePoint);
    System.out.println(new Date() + " This should be a low number: " + msAccuracy);
    if (msAccuracy > 1000) System.out.println(new Date() + " This appears to be operating incorrectly...the expected sleep time has NOT been achieved.");
    System.out.println(new Date() + " Program is ending.");
}
}

我意识到我可以尝试各种其他方法来睡觉,但我认为,因为我经历并记录了这一点,我会在尝试其他事情之前在此发布.

附加信息：此故障似乎也出现在Windows 8中(但不是7或更早).

最佳答案 这是预期的有效行为.
documentation是非常明确的,说明：

these sleep times are not guaranteed to be precise, because they are limited by the facilities provided by the underlying OS.

和：

In any case, you cannot assume that invoking sleep will suspend the thread for precisely the time period specified.

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