[Zope3-dev] ZEO and Zope 3.2

[Jim Fulton]

Jim Fulton wrote:
> Stephan Richter wrote:
> 
....

>  > but then Jim just figured out that there
> 
>> is no problem. ;-)
> 
> 
> Oh, there is a problem.  It's not readily apparent though.  But, don't
> worry, I'll figure out why I can't see a problem that I know is there. :)

If you use the Rotterdam skin, there will appear to be no problem. This
is because of a bug in the skin that causes a database access on every page
view.  If I fix that bug, then I can see a problem. The problem isn't as
pronounced as I'd feared, as ZODB managed to do a good job of staying up
to date even without the asyncore main loop.  (It aranges to explicitly
synchronize at the end of each transaction. In fact, if it did the same
at the start of each transaction, we'd probably be golden.)  The symptom
is that the first web requests that doesn't update any information or
make any uncached database calls and that is the first request after
another ZEO client updated the database may see out of date information.

So, we still do need a fix for the ZEO problem.

I'll check in the skin fix. The bug slowed down non-management
display of a folder with 9 items by around 20%.

Jim

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