sathya wrote:

we have been looking at psycopg for postgres. zope opens atleast one connection per zope thread. I have obeserved the same for mysql as well. Are you creating your own threads within zope ? in which case you have to do the locking yourself Brad Clements wrote:

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I am using ZsapdbDA with SAPDB (now MaxDB) and have run into problems when Zope has more than one thread.

The folks at SAP suggest that there should be one database connection per thread, rather than sharing one connection across threads.

I haven't yet looked at the Zsapdb source, but I think it has only one connection for all threads.

Is there a document somewhere that explains how to make variables "thread private" in Zope? I vaguely recall something about one cache per thread, or that variables are read- only shared unless updated by a thread, and then they're copied.. This is probably quite wrong, but obviously I just don't understand how data and threading works in Zope.

So, I'm looking for a document that explains this clearly. How to have data that is not shared between threads (perhaps a kind of connection pool thingy).

Also, I have other projects where I really want to have just one object of it's kind no matter how many threads. For example, gvibDA uses Thunked_TM for this, but that doesn't really work with ZSQLDA because I've seen that multiple connect calls are made, even with the THUNKED_TM.

Is there a "Zen Of" document about this somewhere?

Thanks