Open Stack

On Wed, Sep 02, 2015 at 04:33:36PM +1200, Robert Collins wrote:
> On 2 September 2015 at 11:53, Angus Salkeld <asalkeld at mirantis.com> wrote:
> 
> > 1. limit the number of resource actions in parallel (maybe base on the
> > number of cores)
> 
> I'm having trouble mapping that back to 'and heat-engine is running on
> 3 separate servers'.

I think Angus was responding to my test feedback, which was a different
setup, one 4-core laptop running heat-engine with 4 worker processes.

In that environment, the level of additional concurrency becomes a problem
because all heat workers become so busy that creating a large stack
DoSes the Heat services, and in my case also the DB.

If we had a configurable option, similar to num_engine_workers, which
enabled control of the number of resource actions in parallel, I probably
could have controlled that explosion in activity to a more managable series
of tasks, e.g I'd set num_resource_actions to (num_engine_workers*2) or
something.

Steve