A smoke break later, some possible more thoughts and snake oil, there are two general purpose facilities embodied in xron that i would like to see made available as zope services, async zope processing and scheduling. async-- i'd like to be able to designate TTW that a method execute outside of the current request/response pair to do some long/heavy processing. the design might be easier if this functionality was separated out. a small dynamic pool of publishing threads to execute async functionality (hmmm.. why reinvent the wheel, zope threads are already in place... but what are the consequences of tying up the fixed number of zope's standard publishing threads on a busy site). and a scheduling thread to manage scheduled events/scheduling and dispatching to publishing threads. the possiblities of such are complicated by the magic number limit of thread connections to the ZODB. I was wondering how this magic number came about, is it a performance number dictated by the python interpretor lock?