Allow concurrent run of event in channels

[clement-michelet]

For independant process, we should be able to parallelize events.

[pdenis]

This can be complex because some events are dependant in the same channels.

We can introduce a flag in the channel configuration to identify channels with independant events.

We can use symfony process to create some differents processes. We must add a parameter to limit the number of process.

What is your point of view?

[juchi]

I think this will be partially solved with the creation of dynamic channels (because they would be independent by definition).
I agree using symfony/process to run parallel tasks seems to be the way to go here.