Dmitry,
Yes, this can be implemented using services in many cases, but:
- It will require user to implement actual scheduling logic. It's quite a
generic task, so I think it makes sense to have it directly on the API.
- Most likely it will imply deploying separate service for each scheduled
task. I don't think it's a very good idea.
- Current services implementation is not durable. If cluster is restarted,
all services are lost.
-Val
On Sat, Jul 1, 2017 at 12:34 AM, Dmitriy Setrakyan <dsetrak...@apache.org>
wrote:
> Val,
>
> In this case, we should have a notion of a named scheduler and ensure that
> we don't schedule the same task more than once. This is beginning to look
> more like a durable cluster singleton service, no?
>
> D.
>
> On Fri, Jun 30, 2017 at 1:39 PM, Valentin Kulichenko <
> valentin.kuliche...@gmail.com> wrote:
>
> > I think this functionality should provide durable way of scheduled task
> or
> > closure execution on the cluster. Job descriptors should be persisted on
> > server side and executed there.
> >
> > As for API, I believe this should be part of Compute Grid. I suggest to
> > introduce IgniteCompute#withSchedulingPolicy(SchedulingPolicy policy)
> > method, where SchedulingPolicy is smth like this:
> >
> > public interface SchedulingPolicy {
> > /**
> > * @return Timestamp of next execution.
> > */
> > public Date nextTime();
> > }
> >
> > This will enable scheduling for all compute features (tasks, callables,
> > closures, etc.) and also very flexible. Policy implementation can provide
> > simple periodic scheduling, scheduling based on Cron or anything else.
> >
> > Thoughts?
> >
> > -Val
> >
> > On Fri, Jun 30, 2017 at 7:55 AM, Dmitriy Setrakyan <
> dsetrak...@apache.org>
> > wrote:
> >
> > > On Fri, Jun 30, 2017 at 12:29 AM, Alexey Kuznetsov <
> > akuznet...@apache.org>
> > > wrote:
> > >
> > > > Dmitriy,
> > > >
> > > > >> Can you provide a simple example of API calls that will make this
> > > > possible?
> > > > API could be like this:
> > > > 1) via scheduler:
> > > > Ignite ignite = Ignition.start(....);
> > > >
> > > > ignite.scheduler().schedulel(job, "0 0 * * *"); // This will execute
> > job
> > > > every day at 00:00
> > > >
> > > > 2) via compute
> > > >
> > > > Ignite ignite = Ignition.start(....);
> > > >
> > > > ignite.compute().schedulel(task, "0 0 * * *"); // This will execute
> > > > compute
> > > > task every day at 00:00
> > > >
> > > > Make sense?
> > > >
> > > >
> > > Yes, it does, but I am failing to see how is this a *distributed*
> > > scheduling. Are we persisting the scheduler somewhere in the cluster or
> > is
> > > it only triggered on the client side?
> > >
> >
>
