On 12/07/2010 10:26 AM, Konstantin Shvachko wrote:
I no longer think we should add any new serialization implementations to
the kernel.
Not clear. Do you propose to keep current serialization(s) and not add new
ones?
Or do you propose to replace current serialization by abstract interfaces
and move implementations to libraries?
We can't move existing serialization implementations to an optional
library without breaking compatibility. Long-term that might be nice,
but I am not proposing that short-term. Short-term I propose we avoid
adding new serialization implementations to the default classpath,
especially those that add new dependencies to every task. Long-term we
might split library code into perhaps a few categories:
- mandatory: this might include, e.g., IdentityMapper and
IdentityReducer, the default implementations.
- back-compatible: the collection of library components that were
provided on the default classpath and can be enabled for back-compatible
behavior.
- optional: components that jobs can optionally depend on. This is
where new components that are not mandatory would be added.
Doug
