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https://issues.apache.org/jira/browse/THRIFT-3768?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15224861#comment-15224861
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Ted Wang commented on THRIFT-3768:
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>> The onClientConnected() method is documented to require the implementation
>> to manage the lifetime of the client object
I don't think the server leaf classes are responsible for managing the lifetime
of the client object because
onClientDisconnected says that "The implementation must not delete the
pointer", and I take it to mean that TServerFramework is responsible for its
lifetime. I take the documentation in onClientConnected to mean that the leaf
classes must take care not to use the client after onClientDisconnected returns.
>> I'd like to get rid of TThreadedServer however... perhaps we can deprecate
>> it in 0.10.0? Using a TThreadPoolServer is a better choice.
I'll just say that TThreadedServer and TThreadPoolServer are very similar in
that one is bounded and another is unbounded. TThreadedServer has a simpler
implementation, but that simplification seems to be flaky in shutdown cases.
By the way, in one of your earlier edits, I think you are running into this
problem:
https://issues.apache.org/jira/browse/THRIFT-3753
> 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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