[ZODB-Dev] Object disappearing -- scary ZODB problem! Please help!!!

[Jens Vagelpohl]

On 23 Nov 2005, at 17:28, Dirksen Lau wrote:
>
> On 11/23/05, Jens Vagelpohl <jens at dataflake.org> wrote:
>>
>> On 23 Nov 2005, at 17:06, Dirksen Lau wrote:
>>> 1. Open the ZMI of the root;
>>> 2. Create one object of whatever type (such as a DTML method);
>>> 3. Keep refreshing the browser. 4 out of 10 the new object  
>>> disappears
>>> from the folder content list! If I surf dirrectly to the object,  
>>> such
>>> as localhost/foo, I'd get 404 too if I keep refreshing the page.
>>> 4. If I open the UNDO log, the add record is always there, so looks
>>> like the ZODB is intact.
>>> 5. It happens to delesion as well, i.e. the deleted object re- 
>>> appears
>>> after some times of refreshing.
>>> 6. It's very illusive. I can reproduce it on two Zope instances  
>>> on the
>>> same machine, but not on other 3. After I restart those affected  
>>> two,
>>> the sympton is just gone.
>>>
>>> Any idea what's happening?
>>
>> It's probably browser caching. Your browser gives you stale data.
> If that's the case, why restarting zope fixes the problem? And double
> check on my IE configuration, the cache is set to 'check for newer
> versions of stored pages on every visit ot the page'.

I trust those settings in the browser as far as I can throw them,  
err, their developers. Especially with IE, which is nearly  
unpredictable when it comes to browser caching.

jens