Besides DeadlockDebugger, is there a way to see just how many threads Zope is currently using ?
What do you mean by 'currently using'? Zope instance always uses the number of threads you've specified in zope.conf. You may try 'ps -aux|grep zope' if you're on linux box. If you want to see what threads are doing then I don't know other tool than DeadlockDebugger for this. Or... the manual solution... you may edit a method in ZMySQLDA (possibly query in db.py) to print some statements before and after it queries the database. Eg. import thread print 'before executing query. thread id: %s' % (thread.get_ident()) r = c.execute() # or something that queries db print 'after executing query. thread id: %s' % (thread.get_ident()) I don't remember exactly how to display thread id so check this because the code above may be broken! You should start your zope in console with runzope or runzope.bat - you'll she statements from db.py. Of course you may write these to files with logging module or something if you don't want to use runzope. When zope "hangs" you may take a look at your console or file to see what is the state of threads. HTH -- Maciej Wisniowski