On 09.10.2006, at 17:40, Tres Seaver wrote:
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Christian Zagrodnick wrote:Hi there, the DB.open method makes me wonder how it works (http://svn.zope.org/ZODB/trunk/src/ZODB/DB.py?rev=69551&view=auto)It locks with self._a() and calls self._connectionMap which locks too. Icannot imagine a way this could possibly work. I guess the lock should be released before the _connectionMap call? Interestingly both all the tests pass and ZODB works...Note the following in the __init__():: # Allocate lock. x = threading.RLock() self._a = x.acquire self._r = x.release The lock is a "reentrant" lock[1], which means that subsequent locks from within the same thread do not deadlock; instead, they increment the lock count. [1] http://docs.python.org/lib/module-threading.html#l2h-3418
Right. *removing blindfold* This explains something :) Thanks for the note.
Actually I came to that lock while investigating Ape for ZODB 3.6 where it in some way actually *did* lock. But I'll investigate that later.
-- Christian Zagrodnick gocept gmbh & co. kg · forsterstrasse 29 · 06112 halle/saale www.gocept.com · fon. +49 345 12298894 · fax. +49 345 12298891
smime.p7s
Description: S/MIME cryptographic signature
_______________________________________________ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org http://mail.zope.org/mailman/listinfo/zodb-dev
