[ZODB-Dev] BTrees and Mutables, was Re: [IndexedCatalog] bug in default indexing

[Guido van Rossum]

> > From what I can tell it is _slow_, or at least much slower than the
> > builtin python list and using _p_changed.
> 
> Possibly. PersistentList puts the content into its own persistent object. It 
> gets its own oid, seperate activation, and its own entry in the pickle cache 
> and ZEO cache.
> 
> This is a significant overhead if your list is small, but a possible 
> scalability advantage depending on access patterns, particularly if your list 
> is large.

But the the __setitem__ etc. methods implemented in Python
is always much slower than setting _p_changed to 1 manually.

--Guido van Rossum (home page: http://www.python.org/~guido/)