[Zope] Re: ZODB caching issue

[Dieter Maurer]

David Chandek-Stark wrote at 2005-5-12 15:31 -0400:
>Dieter Maurer wrote:
>>>Symptom:
>>>  When a new item is added to the RSS feed (b/c a news item was 
>>>published), my ZPT displays the RSS data inconsistently with each 
>>>browser refresh -- sometimes the new item appears, sometimes not.
>> 
>> 
>> A bug in "RDFSummary" which uses a ZODB cache to maintain
>> the fetched items.
>> Unfortunately, each connection has its own independent ZODB cache....
>> 
>> Using a ZODB cache for this use case is both inefficient
>> and error prone.
>> 
>> You should contact the "RDFSummary" authors.
>> 
>
>As mentioned in the original post, I am now using CMFSin and having the 
>smae problem. Are you saying that this is an issue with the design of 
>the product?

I am saying what I said: "RDFSummary" caches with "_v_" variables
i.e. it uses a ZODB cache and ZODB caches are difficult to
synchronize between workers. This easily leads to such inconsistencies
as you have described them.

Other products may make the same error.

I do not know "CMFSin". Therefore, I cannot tell you that it does.
But, it you see what you had described, there is a not so small
chance ...

-- 
Dieter