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Re: Yarn job stuck with no application master being assigned
Siddhi,

On Jun 21, 2013, at 6:07 PM, Siddhi Mehta <[EMAIL PROTECTED]> wrote:

> That solved the problem. Thanks Sandy!!
>
> What is the optimal setting for yarn.scheduler.capacity.maximum-am-resource-percent in terms of node manager.
> What are the consequences of setting to a higher value?

This means that more AMs will be active concurrently.

One thing to remember: in terms of getting *real* work done an AM is, kinda, pure overhead (currently) in the sense that it does not do actual data-processing - this is true of the MR AM; but really depends on how the AM is implemented. An AM *may* choose to do some actual work of course - depends on the implementation.

With that context, If you have a very small cluster, then too many containers might be used for running AMs with higher values for yarn.scheduler.capacity.maximum-am-resource-percent and overall utilization might go low. As a result, you want to be aware of this.
> Also, I noticed that by default application master needs 1.5GB. Are there any side effects we will face if I lower that to 1GB
I have tried AMs with as low as 200M for small jobs. It really depends on how many tasks you want your job to manage.

Arun

>
> Siddhi
>
>
> On Fri, Jun 21, 2013 at 4:28 PM, Sandy Ryza <[EMAIL PROTECTED]> wrote:
> Hi Siddhi,
>
> Moving this question to the CDH list.
>
> Does setting yarn.scheduler.capacity.maximum-am-resource-percent to .5 help?
>
> Have you tried using the Fair Scheduler?
>
> -Sandy
>
>
> On Fri, Jun 21, 2013 at 4:21 PM, Siddhi Mehta <[EMAIL PROTECTED]> wrote:
> Hey All,
>
> I am running a Hadoop 2.0(cdh4.2.1) cluster on a single node with 1 NodeManager.
>
> We have an Map only job that launches a pig job on the cluster(similar to what oozie does)
>
> We are seeing that the map only job launches the pig script but the pig job is stuck in ACCEPTED state with no trackingUI assigned.
>
> I dont see any error in the nodemanager logs or the resource manager logs as such.
>
>
> On the nodemanager i see this logs
> 2013-06-21 15:05:13,084 INFO  capacity.ParentQueue - assignedContainer queue=root usedCapacity=0.4 absoluteUsedCapacity=0.4 used=memory: 2048 cluster=memory: 5120
>
> 2013-06-21 15:05:38,898 INFO  capacity.CapacityScheduler - Application Submission: appattempt_1371850881510_0003_000001, user: smehta queue: default: capacity=1.0, absoluteCapacity=1.0, usedResources=2048MB, usedCapacity=0.4, absoluteUsedCapacity=0.4, numApps=2, numContainers=2, currently active: 2
>
> Which suggests that the cluster has capacity but still no application master is assigned to it.
> What am I missing?Any help is appreciated.
>
> I keep seeing this logs on the node manager
> 2013-06-21 16:19:37,675 INFO  monitor.ContainersMonitorImpl - Memory usage of ProcessTree 12484 for container-id container_1371850881510_0002_01_000002: 157.1mb of 1.0gb physical memory used; 590.1mb of 2.1gb virtual memory used
> 2013-06-21 16:19:37,696 INFO  monitor.ContainersMonitorImpl - Memory usage of ProcessTree 12009 for container-id container_1371850881510_0002_01_000001: 181.0mb of 1.0gb physical memory used; 1.4gb of 2.1gb virtual memory used
> 2013-06-21 16:19:37,946 INFO  nodemanager.NodeStatusUpdaterImpl - Sending out status for container: container_id {, app_attempt_id {, application_id {, id: 2, cluster_timestamp: 1371850881510, }, attemptId: 1, }, id: 1, }, state: C_RUNNING, diagnostics: "", exit_status: -1000,
> 2013-06-21 16:19:37,946 INFO  nodemanager.NodeStatusUpdaterImpl - Sending out status for container: container_id {, app_attempt_id {, application_id {, id: 2, cluster_timestamp: 1371850881510, }, attemptId: 1, }, id: 2, }, state: C_RUNNING, diagnostics: "", exit_status: -1000,
> 2013-06-21 16:19:38,948 INFO  nodemanager.NodeStatusUpdaterImpl - Sending out status for container: container_id {, app_attempt_id {, application_id {, id: 2, cluster_timestamp: 1371850881510, }, attemptId: 1, }, id: 1, }, state: C_RUNNING, diagnostics: "", exit_status: -1000,

Arun C. Murthy
Hortonworks Inc.
http://hortonworks.com/