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https://issues.apache.org/jira/browse/THRIFT-3768?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15225199#comment-15225199
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James E. King, III commented on THRIFT-3768:
--------------------------------------------

The behavior of TThreadedServer is a little different now than before.  
Previously it would scale threads up and down to meet demand.  I made it a 
subclass of TThreadPoolServer and it will scale up the number of threads to 
meet demand, up to the limit of concurrent connections imposed by the 
TServerFramework.  What it will not do however is reap those threads.  The 
ThreadManager::removeWorker() is not reliable as written and it was not 
possible to use it to reduce the thread count of the thread manager used by the 
thread pool when a client disconnects.  I will be opening a separate defect for 
that.

> TThreadedServer may crash if it is destroyed immediately after it returns 
> from serve()
> --------------------------------------------------------------------------------------
>
>                 Key: THRIFT-3768
>                 URL: https://issues.apache.org/jira/browse/THRIFT-3768
>             Project: Thrift
>          Issue Type: Bug
>          Components: C++ - Library
>    Affects Versions: 0.9.3
>            Reporter: Ted Wang
>            Assignee: James E. King, III
>            Priority: Minor
>
> Here's a sequence that shows the race:
> Thread-1 (Users of TThreadedServer): Calls TThreadedServer::stop(), which 
> calls interruptChildren and initiates the tearing down of client connections.
> Thread-2: In TServerFramework::serve(), broke out of accept, and now blocks 
> in TThreadedServer::serve() waiting to drain all the clients.
> Thread-3 (The connected client thread created by TThreadedServer): In 
> disposeConnectedClient, running because the server is shutting down and the 
> shared_ptr specified this function to be the cleanup function for the client. 
> This thread just returned from onClientDisconnected and now context switches.
> Thread-2: TThreadedServer::serve() is notified that all of the clients have 
> disconnected and completes.
> Thread-1: Joins on Thread-2 and destroys the server object because it is done.
> Thread-3: Finally gets a chance to run, but now encounters undefined behavior 
> because it is still executing a member function of an object that has been 
> destroyed.
> You can force this race in action if you put sleep(1) before 
> onClientDisconnected() in disposeConnectedClient



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