Hi， I'm a user of Hadoop YARN and these days i'm testing Node LABEL function on YARN 2.8.0 with capacity scheduler. I found that the preemption didn't work on queues with label. Here is the details: 1. I set *test* label to 2 nodes in our cluster. 2. I set *test1*, *test2* queues under root which can only access *test* label. And each queue's accessible-node-labels.test.capacity=50, accessible-node-labels.test.maximum-capacity=100 3. enable the preemption policy: yarn.resourcemanager. scheduler.monitor.enable=true 4. submit a spark task (named A) to queue *test1*, which asks for 16 executors and will use all resource of *test* partition. 5. submit a spark test (named B) to queue *test2*. I assumes that because of the under-satisfied of test2 and over-satisfied of test1, the preemption will happen and each queue will use 50% resource of partition test finally. In fact, the preempting didn't happen and the task B stay in accepted state. when task A finished, task b started to run. 6. submit same task to different queues in default partition and the preemption happens as we expected。
I found that a patch YARN-2498 about preemption have merged to 2.8.0 and i think with this patch YARN supports preemption on labeled partitions. So is there any configure need to set or I made some mistake when i use this function? Or did I misunderstand patch YARN-2498 and in fact 2.8.0 don't support preemption on labeled partitions? Looking forward your reply, thank you. -- Best regards! Ziqian HU 胡子千 Department of Computer Science, School of EECS, Peking University
