On 09/29/2016 07:33 AM, Kevin Wolf wrote:
Am 28.09.2016 um 14:16 hat Vladimir Sementsov-Ogievskiy geschrieben:
I think jobs will need to remain "one coroutine, one job" for now,
but there's no reason why drive-backup or blockdev-backup can't
just create multiple jobs each if that's what they need to do.
(The backup job object could, in theory, just have another job
pointer to a helper job if it really became necessary.)
What's the problem with a job spawning additional coroutines internally?
Jobs already do this all the time (AIO requests are just coroutines in
disguise.)
Mostly I was just pushing back against baking in multi-coroutines
per-job as a default. If you want to add them in your own extensions,
e.g. MultiJob : BlockJob {
Coroutine *extra;
}
then I'm okay with that and realize we already do exactly that. Beyond
that I think complicates the job layer a little more than necessary...
but maybe I am being too pre-fearful.
A job is basically just the user interface for managing a background
process, so helper jobs that are managed internally rather than by the
user don't seem to make that much sense.
Kevin
