just a quick reply, we cannot start two executors in the same host for a single
application in the standard deployment (one worker per machine)
I’m not sure if it will create an issue when you have multiple workers in the
same host, as submitWaitingStages is called everywhere and I never try such a
deployment mode
Best,
--
Nan Zhu
On Friday, September 26, 2014 at 8:02 AM, praveen seluka wrote:
> Can someone explain the motivation behind passing executorAdded event to
> DAGScheduler ? DAGScheduler does submitWaitingStages when executorAdded
> method is called by TaskSchedulerImpl. I see some issue in the below code,
>
> TaskSchedulerImpl.scala code
> if (!executorsByHost.contains(o.host)) {
> executorsByHost(o.host) = new HashSet[String]()
> executorAdded(o.executorId, o.host)
> newExecAvail = true
> }
>
>
> Note that executorAdded is called only when there is a new host and not for
> every new executor. For instance, there can be two executors in the same host
> and in this case. (But DAGScheduler executorAdded is notified only for new
> host - so only once in this case). If this is indeed an issue, I would like
> to submit a patch for this quickly. [cc Andrew Or]
>
> - Praveen
>
>
