Zope 2.8/ZODB 3.3: Update all cPickle.Pickler instances to use protocal 2

[Andreas Jung]

For efficiency we should use pickle protocol 2 instead of protocol 1.

[Tim Peters (tim-one)]

Status: Pending => Accepted

 Supporters added: tim_one

It's on an internal todo list, but has been delayed for two reasons. First, there was a bug in proto 2 that didn't get fixed until Python 2.3.4, so 2.3.4 is an absolute minimum requirement. That delayed even thinking about this seriously for a long time. The other reason still exists: since proto 2 pickles can't be read by older Pythons, then, for example, a Data.fs created after switching to proto 2 can't be used under any older Zope/ZODB installation. That hard incompatibility makes it seem prudent to wait on this a bit longer.

[Federico G. Schwindt (fgsch)]

Can this be added as an option, and by default set it to 1 (for backward compatibility)?
This way people has the option to use protocol 2, if they don't care about backward compatibility and run with python 2.3.4 or newer (I'd assume most people by now).

[Tim Peters (tim-one)]

Unassigned myself -- I haven't done ZODB work in nearly 3 years :-(

[Federico G. Schwindt (fgsch)]

Anyone? Newer zope won't even work with old python versions so why is this sitting here?