[Spread-users] Spread python module

Yair Amir yairamir at cnds.jhu.edu
Thu Apr 18 08:43:34 EDT 2002


I suspect you do need the fix. The fix, as I understand it, fixes a
race condition in the module that occurs when Spread disconnects the
client. The reason Spread disconnects the client is probably lack of
flow control at the application that results in a client not reading
fast enough from Spread and being disconnected.

But it does not make much sense to me. Can you verify it it works
with Python2.2.1, Spread 3.16.1 and SpreadModule1.1?

	:) Yair.

Magnus Heino wrote:

> Hi.
> I have a multithreaded app written in python that uses spread and the python 
> spread module.
> Versions this morning were Python2.2, Spread 3.16.1 and SpreadModule1.0
> I have now upgraded to Python2.2.1, Spread 3.16.2 and SpreadModule1.1
> After the upgrade, multicast locks. Not everytime, but at some places in the 
> code. After a revert back to 3.16.1 and SpreadModule 1.0, it works again, so 
> its not Python2.2.1 thats causing it. 
> Looking at the diff between SpreadModule 1.0 and 1.1, the major difference is 
> this;
> - Fixed race conditions having to do with disconnects in
>   multi-threaded programs.  When one of the errors CONNECTION_CLOSED
>   or ILLEGAL_SESSION is received, mark the mbox as closed.  In
>   addition, use a lock to serialize access to the disconnected flag.
> Is this needed in 3.16.2 too? The SpreadModule is written against 3.16.2rc1

More information about the Spread-users mailing list