BlockedIndefinitelyOnMVar exception

Neil Mitchell ndmitchell at
Sat Jun 26 07:28:12 EDT 2010


I have a very big and highly threaded program that generates a
BlockedIndefinitelyOnMVar exception when run. I have spent a
reasonable amount of time pouring over the source code, as has Max
Bolingbroke. Neither of us have the slightest idea why it raises the

Some questions:

* Does anyone know the exact sequence of actions that causes this
exception to be thrown? I couldn't find it written down.
* How confident are people that this exception does really mean that
it is in a blocked state? Is there any chance the error could be
raised incorrectly?
* Any debugging tips for this problem?

Thanks, Neil

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