Re: psycopg2 multiprocessing problem
Federico Di Gregorio <fog-NGVKUo/i/[email protected]>
| Newsgroups | gmane.comp.python.db.psycopg.devel |
|---|---|
| Message-ID | <[email protected]> |
On 07/02/2010 19:43, kevin wrote: > i am getting this error message in pg_log log directory > > http://pastie.org/813651 > > i do not think there are any error in the queries [select, insert/updates] i > am doing, because if i switch to threading instead of multiprocessing i dont > get any error at all. but i want to use multiprocessing. It seems you're using the same connection from two processes at the same time. Threads use the same address space, so they can share the connection because locks and shared state works. I suppose the fork() done by multiprocess duplicates file descriptors so that the pq connection continue to work but now you have two python connections that don't share the same state anymore and this is bad (no locking and so on). Just create a new connection in every process. psycopg law number 0: never share a connection between processes. federico -- Federico Di Gregorio fog-NGVKUo/i/[email protected] There's no certainty - only opportunity. -- V _______________________________________________ Psycopg mailing list Psycopg-IAPFreCvJWPBWskQ1e/[email protected] http://lists.initd.org/mailman/listinfo/psycopg
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