I can reproduce it instantly with a large enough page - stop the request mid-way, the closing of the socket to the client while Zope is serving the page up seems to be what causes it to go into it's loop, then die.
Is this only when accessing via FastCGI or does happen when using ZServer as well?
Just for the record, I dont' use FastCGI and have seen Zope die under the same circumstances; ie. by disconnecting the browser mid-download of a (usually long) page. Fortunately, that 'client' has been me via the administration screens, but it does seem like a rather trivial DoS. But it seems that this only happens with certain types of pages - I'm not sure which. Unfortunately, I can't remember if this was when we were using PCGI or Proxy-Pass, but it was definitely one of the two. Hearing that others are now experiencing the same gives me hope: this could explain the crashes that we've been plagued with for months (though I fear any solution will come too late to prevent our switch to an alternative platform). chas ps. Weird thing : the most stable Zope installation I have is on NT. It never, ever crashes, despite being the development machine (I wouldn't say that load is causing my production server to die b/c it happens under low load too).