配置符号文件

SRV*D:\symbols*http://msdl.microsoft.com/download/symbols

.load c:\WINDOWS\Microsoft.NET\Framework64\v2.0.50727\sos.dll

检查堆栈：

Examine the stacks

1. Examine the native callstacks

~* kb 2000

2. Examine the .net callstacks

~* e !clrstack

Q: Do you see any patterns or recognize any of the callstacks that suggests a thread is waiting for a synchronization mechanism?

Troubleshoot the hang

1. Determine the ID of the thread owning the lock

!syncblk

Q: What thread owns the lock?

Q: How many threads are waiting for the lock?

Hint: MonitorHeld = 1 for each owner and 2 for each waiter.

2. Pick one of the waiters (Hint: waiters will sit in AwareLock::Enter) and take a look at what it is doing.

~5s (move to thread 5, replace 5 with actual thread ID)

kb 2000 (examine native stack)

!clrstack (examine .net stack)

Q: In which .net function is it waiting for the lock?

3. Determine what the owning thread is doing

~5s (move to thread 5, replace 5 with actual thread ID)

kb 2000 (examine native stack)

!clrstack (examine .net stack)

Q: Why is it blocking?

4. Examine the code for .NET method owning the lock to verify your theory.