Hi Avery, I am setting "minsharepreemptiontimeout" to 5 sec and my Giraph job could not even wait for 5 secs to get its slots. Let me explain the scenario below:
Assume, Cluster capacity is 150 Queue A (min share –10 maps) - I submit a sleep job with 100 map tasks. Cluster is empty, and hence the first job submitted to Queue A will take the entire 100 map tasks. Queue B (Giraph pool with min share – 140 maps) - Now my job 1 is running with 100 tasks occupied. I submit a giraph shortestpathfirst example job with 100 workers to Queue B. Queue B has "minsharepreemptiontimeout" to 5 sec". So, it will first schedule 50 tasks since first job only took 100 tasks and cluster's capacity is 150. Meanwhile, in 5 sec, 50 more tasks would be preempted from Queue A and would be given to Giraph Job. I see this happening, however, the job fails with "Unable to create native thread error" Please let me know if "giraph.maxMasterSuperstepWaitMsecs" will help in this scenario. Thanks so much Arun Ramani From: Avery Ching <[email protected]<mailto:[email protected]>> Date: Tuesday, May 7, 2013 2:19 PM To: "[email protected]<mailto:[email protected]>" <[email protected]<mailto:[email protected]>> Cc: "Ramani, Arun(aramani)" <[email protected]<mailto:[email protected]>> Subject: Re: Giraph and Fair Scheduler Oh, I see. You can change the timeout of how long the giraph job waits for tasks before giving up. Try setting giraph.maxMasterSuperstepWaitMsecs to a higher number. The default is 10 minutes. Avery On 5/7/13 2:10 PM, Ramani, Arun wrote: Hi Avery, I am not preempting tasks out of the giraph pool. I have configured pre-emption so that any job submitted to giraph pool will get its min share. Any suggestion on how to make this work? Thanks so much in advance. Arun Ramani From: Avery Ching <[email protected]<mailto:[email protected]>> Reply-To: "[email protected]<mailto:[email protected]>" <[email protected]<mailto:[email protected]>> Date: Tuesday, May 7, 2013 7:25 AM To: "[email protected]<mailto:[email protected]>" <[email protected]<mailto:[email protected]>> Subject: Re: Giraph and Fair Scheduler Can you disable the preemption for the giraph pool? It's not great to preempt those tasks. Avery On 5/6/13 6:37 PM, Ramani, Arun wrote: Hi, I am running Fair scheduler with many applications in hadoop stack in my cluster (like pig, hive, hbase etc). I have dedicated a pool for Giraph and want to run giraph along with those other applications. I have configured pre-emption and and set the "minsharepreemptiontimeout=5" (sec – for the jobs submitted to this pool to wait to get the min share). I am trying to run giraph in this mode. I see that jobs from other pools are getting pre-empted to give the giraph job's pool its configured min share but my job fails with "Unable to create native thread" error. This same job passes if the slots are available immediately without having to wait for the tasks from other queues to be pre-empted. I also tried to tweak the "giraph.minPercentResponded=50.0f". My Giraph job still fails. Please help in this scenario. Basically, I wanted to know how to configure giraph to wait for a threshold for the slots to be available for it through pre-emption. Thanks Arun Ramani
