[Zope-dev] cPickleCache endless loop...

[Mario Lorenz]

Am 26. Jan 2004, um 12:22:43 schrieb Tim Peters:

> It's actually that the number of __del__-resurrecting objects *plus* the
> number of non-ghostifiable objects in cache is larger than the cache target
> size, right?

Yes, but when you push the minimize button, the cache target size is 0.

Nonwithstanding our code (it was mostly debugging/tracing functionality
anyway, so it was easy to fix), it is just that with Zope 2.5, it seemed
to work (at least I never got a bug report back then) so it took us a
while to track this down.
Especially since we had just moved to RHEL3, so we were expecting more like
a threading issue...

Given that this property is not that widely published (in the various
tutorials etc.), I wonder if it might be a good idea to improve that loop
check code, and walk through the ring not more than once, using a counter,
and not the comparison vs. the ring start, which, as we have seen, may be a
target that moves too quickly.

> Similarly <wink>, except that if there's a large number of non-ghostifiable
> objects (more than the cache target size), then only one __del__-resurrected
> object is enough to provoke an infinite loop.

Yes, this is exactly what happened here.

Mario

-- 
Mario Lorenz              EMail:   Mario.Lorenz at km3.de
                            Tel:   03774 6625-78
Technik Netze             Handy:   0160 3151600
km3 teledienst GmbH         Fax:   03774 6625-79