[ 
https://issues.apache.org/jira/browse/YARN-5039?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15271405#comment-15271405
 ] 

Jason Lowe commented on YARN-5039:
----------------------------------

If it tries to satisfy a reservation and fails to do so then that implies there 
are insufficient resources on the node to satisfy the request.  In this case 
it's trying to allocate a 50GB container, but unfortunately the logs don't show 
how much space is available on those nodes.  Since there are insufficient 
resources it re-reserves the node, and that causes subsequent scheduling on 
that node to be skipped due to the unsatisfied reservation.  If none of the 
nodes in the cluster can fit another 50GB container then that explains the 
delay.

If there are nodes in the cluster that can satisfy the 50GB request but it 
still fails to do so then that indicates either 
yarn.scheduler.capacity.reservations-continue-look-all-nodes=false (true by 
default) or there's a bug.  Recently there were some problems with 
reservations-continue-look-all-nodes that caused delayed scheduling, see 
YARN-4610.



> Applications ACCEPTED but not starting
> --------------------------------------
>
>                 Key: YARN-5039
>                 URL: https://issues.apache.org/jira/browse/YARN-5039
>             Project: Hadoop YARN
>          Issue Type: Bug
>    Affects Versions: 2.7.2
>            Reporter: Miles Crawford
>
> Often when we submit applications to an incompletely utilized cluster, they 
> sit, unable to start for no apparent reason.
> There are multiple nodes in the cluster with available resources, but the 
> resourcemanger logs show that scheduling is being skipped. The scheduling is 
> skipped because the application itself has reserved the node? I'm not sure 
> how to interpret this log output:
> {code}
> 2016-05-04 20:19:21,315 INFO 
> org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacityScheduler
>  (ResourceManager Event Processor): Trying to fulfill reservation for 
> application application_1462291866507_0025 on node: 
> ip-10-12-43-54.us-west-2.compute.internal:8041
> 2016-05-04 20:19:21,316 INFO 
> org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.LeafQueue 
> (ResourceManager Event Processor): Reserved container  
> application=application_1462291866507_0025 resource=<memory:50688, vCores:1> 
> queue=default: capacity=1.0, absoluteCapacity=1.0, 
> usedResources=<memory:1894464, vCores:33>, usedCapacity=0.7126589, 
> absoluteUsedCapacity=0.7126589, numApps=2, numContainers=33 
> usedCapacity=0.7126589 absoluteUsedCapacity=0.7126589 used=<memory:1894464, 
> vCores:33> cluster=<memory:2658304, vCores:704>
> 2016-05-04 20:19:21,316 INFO 
> org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacityScheduler
>  (ResourceManager Event Processor): Skipping scheduling since node 
> ip-10-12-43-54.us-west-2.compute.internal:8041 is reserved by application 
> appattempt_1462291866507_0025_000001
> 2016-05-04 20:19:22,232 INFO 
> org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacityScheduler
>  (ResourceManager Event Processor): Trying to fulfill reservation for 
> application application_1462291866507_0025 on node: 
> ip-10-12-43-53.us-west-2.compute.internal:8041
> 2016-05-04 20:19:22,232 INFO 
> org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.LeafQueue 
> (ResourceManager Event Processor): Reserved container  
> application=application_1462291866507_0025 resource=<memory:50688, vCores:1> 
> queue=default: capacity=1.0, absoluteCapacity=1.0, 
> usedResources=<memory:1894464, vCores:33>, usedCapacity=0.7126589, 
> absoluteUsedCapacity=0.7126589, numApps=2, numContainers=33 
> usedCapacity=0.7126589 absoluteUsedCapacity=0.7126589 used=<memory:1894464, 
> vCores:33> cluster=<memory:2658304, vCores:704>
> 2016-05-04 20:19:22,232 INFO 
> org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacityScheduler
>  (ResourceManager Event Processor): Skipping scheduling since node 
> ip-10-12-43-53.us-west-2.compute.internal:8041 is reserved by application 
> appattempt_1462291866507_0025_000001
> 2016-05-04 20:19:22,316 INFO 
> org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacityScheduler
>  (ResourceManager Event Processor): Trying to fulfill reservation for 
> application application_1462291866507_0025 on node: 
> ip-10-12-43-54.us-west-2.compute.internal:8041
> 2016-05-04 20:19:22,316 INFO 
> org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.LeafQueue 
> (ResourceManager Event Processor): Reserved container  
> application=application_1462291866507_0025 resource=<memory:50688, vCores:1> 
> queue=default: capacity=1.0, absoluteCapacity=1.0, 
> usedResources=<memory:1894464, vCores:33>, usedCapacity=0.7126589, 
> absoluteUsedCapacity=0.7126589, numApps=2, numContainers=33 
> usedCapacity=0.7126589 absoluteUsedCapacity=0.7126589 used=<memory:1894464, 
> vCores:33> cluster=<memory:2658304, vCores:704>
> 2016-05-04 20:19:22,316 INFO 
> org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacityScheduler
>  (ResourceManager Event Processor): Skipping scheduling since node 
> ip-10-12-43-54.us-west-2.compute.internal:8041 is reserved by application 
> appattempt_1462291866507_0025_000001
> {code}



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]

Reply via email to