.net - 当前逻辑线程增加/线程堆栈泄漏

Question

在性能监视器中监视我的.NET应用程序，我可以看到 .NET CLR LocksAndThreads/当前逻辑线程数随着时间的推移稳步增加(当前为293)，这表明线程堆栈正在泄漏。

我可以找到许多文章来告诉我这是问题所在，但没有什么能告诉我如何找到原因-那我应该从哪里开始呢？ Windbg可以告诉我问题出在哪里吗？

这是我在3小时内的性能监视器，告诉我当前的逻辑线程为150:

这是线程窗口的输出，不会告诉我太多，因为我无法访问它们的调用堆栈-它们大多标记为[不可用]或[正在 sleep ，等待或加入]。 [外部代码]:

Unflagged       141024  124 Worker Thread   <No Name>       Normal
Unflagged   >   0   0   Unknown Thread  [Thread Destroyed]      
Unflagged       136272  2   Worker Thread   <No Name>       Highest
Unflagged       133060  7   Worker Thread   vshost.RunParkingWindow [Managed to Native Transition]  Normal
Unflagged       136952  10  Main Thread Main Thread [edited].Program.Main   Normal
Unflagged       134544  9   Worker Thread   .NET SystemEvents   [Managed to Native Transition]  Normal
Unflagged       136556  11  Worker Thread   Worker Thread   [edited].MessageService.ProcessJobs.AnonymousMethod__0  Normal
Unflagged       141364  113 Worker Thread   <No Name>   [In a sleep, wait, or join] Normal
Unflagged       140896  0   Worker Thread   [Thread Destroyed]      Normal
Unflagged       136776  19  Worker Thread   <No Name>   [In a sleep, wait, or join] Normal
Unflagged       135704  20  Worker Thread   <No Name>   [In a sleep, wait, or join] Normal
Unflagged       136712  21  Worker Thread   <No Name>   [In a sleep, wait, or join] Normal
Unflagged       134984  22  Worker Thread   <No Name>   [In a sleep, wait, or join] Normal
Unflagged       134660  23  Worker Thread   Worker Thread   [edited].BroadcastService.ProcessJobs.AnonymousMethod__1d   Normal
Unflagged       140224  152 Worker Thread   <No Name>       Normal
Unflagged       140792  157 Worker Thread   <No Name>       Normal
Unflagged       137116  0   Worker Thread   <No Name>       Normal
Unflagged       140776  111 Worker Thread   <No Name>       Normal
Unflagged       140784  0   Worker Thread   [Thread Destroyed]      Normal
Unflagged       140068  145 Worker Thread   <No Name>       Normal
Unflagged       139000  150 Worker Thread   <No Name>       Normal
Unflagged       140828  52  Worker Thread   <No Name>       Normal
Unflagged       137752  146 Worker Thread   <No Name>       Normal
Unflagged       140868  151 Worker Thread   <No Name>       Normal
Unflagged       141324  139 Worker Thread   <No Name>       Normal
Unflagged       140168  154 Worker Thread   <No Name>       Normal
Unflagged       141848  0   Worker Thread   [Thread Destroyed]      Normal
Unflagged       135544  153 Worker Thread   <No Name>       Normal
Unflagged       142260  140 Worker Thread   <No Name>       Normal
Unflagged       141528  142 Worker Thread   <No Name>   [In a sleep, wait, or join] Normal
Unflagged       141344  0   Worker Thread   [Thread Destroyed]      Normal
Unflagged       140096  136 Worker Thread   <No Name>       Normal
Unflagged       141712  134 Worker Thread   <No Name>       Normal
Unflagged       141688  147 Worker Thread   <No Name>       Normal

更新:
从那以后，我一直跟踪到罪魁祸首到System.Timers.Timer。即使该计时器在每个Elapsed事件上调用了一个空方法，它仍会无限期地增加逻辑线程数。只需将计时器更改为DispatcherTimer即可解决此问题。

如 this question中所述，在Windbg中运行 !dumpheap -type TimerCallback时看到了很多计时器后，便开始研究应用程序中的所有计时器。

我仍然想知道如何通过Windbg调试而不是通过导致我修复的disable timers/check performance/repeat方法来检测到该错误。 IE。可以告诉我哪个计时器造成了问题的所有信息。

Answer 1

这通常是由于线程池线程卡住而无法完成引起的。每半秒钟，线程池管理器允许另一个线程开始尝试减少积压。这一直持续到达到ThreadPool.SetMaxThreads()设置的最大线程数为止。默认情况下，数量巨大，四核计算机上为1000。

使用Debug + Windows + Threads查看正在运行的线程。他们的通话堆栈应该清楚表明他们为什么要阻塞。