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Íñigo Goiri commented on YARN-11191: ------------------------------------ Do you mind preparing a PR? Is it possible to add a test? > Global Scheduler refreshQueue cause deadLock > --------------------------------------------- > > Key: YARN-11191 > URL: https://issues.apache.org/jira/browse/YARN-11191 > Project: Hadoop YARN > Issue Type: Bug > Components: capacity scheduler > Affects Versions: 2.9.0, 3.0.0, 3.1.0, 2.10.0, 3.2.0, 3.3.0 > Reporter: ben yang > Priority: Major > Attachments: 1.jstack, YARN-11191.001.patch > > > This is a potential bug may impact all open premmption cluster.In our > current version with preemption enabled, the capacityScheduler will call the > refreshQueue method of the PreemptionManager when it refreshQueue. This > process hold the preemptionManager write lock and require csqueue read > lock.Meanwhile,ParentQueue.canAssignToThisQueue will hold csqueue readLock > and require PreemptionManager ReadLock. > There is a possibility of deadlock at this time.Because readlock has one rule > on unfair policy, when a lock is already occupied by a read lock and the > first request in the lock competition queue is a write lock request,other > read lock requests cann‘t acquire the lock. > So the potential deadlock is: > {code:java} > CapacityScheduler.refreshQueue: hold: PremmptionManager.writeLock > require: csqueue.readLock > CapacityScheduler.schedule: hold: csqueue.readLock > require: PremmptionManager.readLock > other thread(completeContainer,release Resource,etc.): require: > csqueue.writeLock > {code} > The jstack logs at the time were as follows -- This message was sent by Atlassian Jira (v8.20.10#820010) --------------------------------------------------------------------- To unsubscribe, e-mail: yarn-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: yarn-issues-h...@hadoop.apache.org