[Engine-devel] Managing async tasks

[Adam Litke]

On today's vdsm call we had a lively discussion around how asynchronous
operations should be handled in the future.  In an effort to include more people
in the discussion and to better capture the resulting conversation I would like
to continue that discussion here on the mailing list.

A lot of ideas were thrown around about how 'tasks' should be handled in the
future.  There are a lot of ways that it can be done.  To determine how we
should implement it, it's probably best if we start with a set of requirements.
If we can first agree on these, it should be easy to find a solution that meets
them.  I'll take a stab at identifying a first set of POSSIBLE requirements:

- Standardized method for determining the result of an operation

  This is a big one for me because it directly affects the consumability of the
  API.  If each verb has different semantics for discovering whether it has
  completed successfully, then the API will be nearly impossible to use easily.


Sorry.  That's my list :)  Hopefully others will be willing to add other
requirements for consideration.

>From my understanding, task recovery (stop, abort, rollback, etc) will not be
generally supported and should not be a requirement.



-- 
Adam Litke <agl at us.ibm.com>
IBM Linux Technology Center