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.