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Posted to issues@ozone.apache.org by GitBox <gi...@apache.org> on 2021/06/01 10:34:38 UTC

[GitHub] [ozone] bshashikant opened a new pull request #2295: HDDS-5284. [SCM-HA] SCM start failed with PipelineNotFoundException.

bshashikant opened a new pull request #2295:
URL: https://github.com/apache/ozone/pull/2295


   ## What changes were proposed in this pull request?
   
   Ignored PipelineNotFoundException in updatePipelineState() call.
   
   ## What is the link to the Apache JIRA
   
   https://issues.apache.org/jira/browse/HDDS-5284
   
   ## How was this patch tested?
   Exusting tests
   


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[GitHub] [ozone] GlenGeng commented on pull request #2295: HDDS-5284. [SCM-HA] SCM start failed with PipelineNotFoundException.

Posted by GitBox <gi...@apache.org>.
GlenGeng commented on pull request #2295:
URL: https://github.com/apache/ozone/pull/2295#issuecomment-852671769


   IMO current fix of ignoring PipelineNotFoundException in updatePipelineState() may not be able to thoroughly handle the contention between EventHandler (StaleNodeHandler, DeadNodeHandler, PipelineActionHandler) and BackgroundPipelineCreatorV2.


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[GitHub] [ozone] GlenGeng commented on pull request #2295: HDDS-5284. [SCM-HA] SCM start failed with PipelineNotFoundException.

Posted by GitBox <gi...@apache.org>.
GlenGeng commented on pull request #2295:
URL: https://github.com/apache/ozone/pull/2295#issuecomment-852035731


   Hey guys, in our production cluster, we meet the similar contention problem, and the consequence is worse: all SCMs crashed at the same time, and can not be restarted again.
   
   The pipeline is `fa2906e2-d989-402f-8148-d9bef3ac5258`,
   
   1, pipeline is created at `14:38:06`
   
   > 2021-05-30 14:38:06,651 [RatisPipelineUtilsThread - 0] INFO org.apache.hadoop.hdds.scm.pipeline.RatisPipelineProvider: Sending CreatePipelineCommand for pipeline:PipelineID=fa2906e2-d989-402f-8148-d9bef3ac5258 to datanode:71935d59-fadc-4951-a08f-035450e70737
   2021-05-30 14:38:06,651 [RatisPipelineUtilsThread - 0] INFO org.apache.hadoop.hdds.scm.pipeline.RatisPipelineProvider: Sending CreatePipelineCommand for pipeline:PipelineID=fa2906e2-d989-402f-8148-d9bef3ac5258 to datanode:0a16a9a7-1af0-4fbe-9b32-9e67df46b4c7
   2021-05-30 14:38:06,651 [RatisPipelineUtilsThread - 0] INFO org.apache.hadoop.hdds.scm.pipeline.RatisPipelineProvider: Sending CreatePipelineCommand for pipeline:PipelineID=fa2906e2-d989-402f-8148-d9bef3ac5258 to datanode:160ad09d-73b5-4392-b08b-3b93befd71d2
   2021-05-30 14:38:06,653 [9e77f811-8df6-4a59-9642-0f40d6f01764@group-58D600BFB107-StateMachineUpdater] INFO org.apache.hadoop.hdds.scm.pipeline.PipelineStateManager: Created pipeline Pipeline[ Id: fa2906e2-d989-402f-8148-d9bef3ac5258, Nodes: 71935d59-fadc-4951-a08f-035450e70737{ip: 11.61.45.54, host: 11.61.45.54, ports: [REPLICATION=9886, RATIS=9858, RATIS_ADMIN=9858, RATIS_SERVER=9858, STANDALONE=9859], networkLocation: /rack582788, certSerialId: null, persistedOpState: IN_SERVICE, persistedOpStateExpiryEpochSec: 0}0a16a9a7-1af0-4fbe-9b32-9e67df46b4c7{ip: 11.26.17.139, host: 11.26.17.139, ports: [REPLICATION=9886, RATIS=9858, RATIS_ADMIN=9858, RATIS_SERVER=9858, STANDALONE=9859], networkLocation: /rack561349, certSerialId: null, persistedOpState: IN_SERVICE, persistedOpStateExpiryEpochSec: 0}160ad09d-73b5-4392-b08b-3b93befd71d2{ip: 11.61.45.51, host: 11.61.45.51, ports: [REPLICATION=9886, RATIS=9858, RATIS_ADMIN=9858, RATIS_SERVER=9858, STANDALONE=9859], networkLocation: /rack5827
 88, certSerialId: null, persistedOpState: IN_SERVICE, persistedOpStateExpiryEpochSec: 0}, Type:RATIS, Factor:THREE, State:ALLOCATED, leaderId:, CreationTimestamp2021-05-30T06:38:06.651Z].
   
   
   2, pipeline action and pipeline scrubber is triggered at the same time, at `14:44:06`, and the pipeline is moved to CLOSED state twice, and removed by one of them.
   
   > 2021-05-30 14:44:06,650 [EventQueue-PipelineActionsForPipelineActionHandler] INFO org.apache.hadoop.hdds.scm.pipeline.PipelineActionHandler: Received pipeline action CLOSE for PipelineID=fa2906e2-d989-402f-8148-d9bef3ac5258 from datanode 0a16a9a7-1af0-4fbe-9b32-9e67df46b4c7. Reason : 0a16a9a7-1af0-4fbe-9b32-9e67df46b4c7 is in candidate state for 304440ms
   2021-05-30 14:44:06,654 [RatisPipelineUtilsThread - 0] INFO org.apache.hadoop.hdds.scm.pipeline.PipelineManagerV2Impl: Scrubbing pipeline: id: PipelineID=fa2906e2-d989-402f-8148-d9bef3ac5258 since it stays at ALLOCATED stage for -6 mins.
   2021-05-30 14:44:06,654 [EventQueue-PipelineActionsForPipelineActionHandler] INFO org.apache.hadoop.hdds.scm.pipeline.PipelineManagerV2Impl: Pipeline Pipeline[ Id: fa2906e2-d989-402f-8148-d9bef3ac5258, Nodes: 71935d59-fadc-4951-a08f-035450e70737{ip: 11.61.45.54, host: 11.61.45.54, ports: [REPLICATION=9886, RATIS=9858, RATIS_ADMIN=9858, RATIS_SERVER=9858, STANDALONE=9859], networkLocation: /rack582788, certSerialId: null, persistedOpState: IN_SERVICE, persistedOpStateExpiryEpochSec: 0}0a16a9a7-1af0-4fbe-9b32-9e67df46b4c7{ip: 11.26.17.139, host: 11.26.17.139, ports: [REPLICATION=9886, RATIS=9858, RATIS_ADMIN=9858, RATIS_SERVER=9858, STANDALONE=9859], networkLocation: /rack561349, certSerialId: null, persistedOpState: IN_SERVICE, persistedOpStateExpiryEpochSec: 0}160ad09d-73b5-4392-b08b-3b93befd71d2{ip: 11.61.45.51, host: 11.61.45.51, ports: [REPLICATION=9886, RATIS=9858, RATIS_ADMIN=9858, RATIS_SERVER=9858, STANDALONE=9859], networkLocation: /rack582788, certSerialId: null, persiste
 dOpState: IN_SERVICE, persistedOpStateExpiryEpochSec: 0}, Type:RATIS, Factor:THREE, State:ALLOCATED, leaderId:, CreationTimestamp2021-05-30T06:38:06.651Z] moved to CLOSED state
   2021-05-30 14:44:06,654 [EventQueue-PipelineActionsForPipelineActionHandler] INFO org.apache.hadoop.hdds.scm.pipeline.RatisPipelineProvider: Send pipeline:PipelineID=fa2906e2-d989-402f-8148-d9bef3ac5258 close command to datanode 71935d59-fadc-4951-a08f-035450e70737
   2021-05-30 14:44:06,654 [EventQueue-PipelineActionsForPipelineActionHandler] INFO org.apache.hadoop.hdds.scm.pipeline.RatisPipelineProvider: Send pipeline:PipelineID=fa2906e2-d989-402f-8148-d9bef3ac5258 close command to datanode 0a16a9a7-1af0-4fbe-9b32-9e67df46b4c7
   2021-05-30 14:44:06,654 [EventQueue-PipelineActionsForPipelineActionHandler] INFO org.apache.hadoop.hdds.scm.pipeline.RatisPipelineProvider: Send pipeline:PipelineID=fa2906e2-d989-402f-8148-d9bef3ac5258 close command to datanode 160ad09d-73b5-4392-b08b-3b93befd71d2
   2021-05-30 14:44:06,657 [RatisPipelineUtilsThread - 0] INFO org.apache.hadoop.hdds.scm.pipeline.PipelineManagerV2Impl: Pipeline Pipeline[ Id: fa2906e2-d989-402f-8148-d9bef3ac5258, Nodes: 71935d59-fadc-4951-a08f-035450e70737{ip: 11.61.45.54, host: 11.61.45.54, ports: [REPLICATION=9886, RATIS=9858, RATIS_ADMIN=9858, RATIS_SERVER=9858, STANDALONE=9859], networkLocation: /rack582788, certSerialId: null, persistedOpState: IN_SERVICE, persistedOpStateExpiryEpochSec: 0}0a16a9a7-1af0-4fbe-9b32-9e67df46b4c7{ip: 11.26.17.139, host: 11.26.17.139, ports: [REPLICATION=9886, RATIS=9858, RATIS_ADMIN=9858, RATIS_SERVER=9858, STANDALONE=9859], networkLocation: /rack561349, certSerialId: null, persistedOpState: IN_SERVICE, persistedOpStateExpiryEpochSec: 0}160ad09d-73b5-4392-b08b-3b93befd71d2{ip: 11.61.45.51, host: 11.61.45.51, ports: [REPLICATION=9886, RATIS=9858, RATIS_ADMIN=9858, RATIS_SERVER=9858, STANDALONE=9859], networkLocation: /rack582788, certSerialId: null, persistedOpState: IN_SERVICE, 
 persistedOpStateExpiryEpochSec: 0}, Type:RATIS, Factor:THREE, State:ALLOCATED, leaderId:, CreationTimestamp2021-05-30T06:38:06.651Z] moved to CLOSED state
   2021-05-30 14:44:06,657 [RatisPipelineUtilsThread - 0] INFO org.apache.hadoop.hdds.scm.pipeline.RatisPipelineProvider: Send pipeline:PipelineID=fa2906e2-d989-402f-8148-d9bef3ac5258 close command to datanode 71935d59-fadc-4951-a08f-035450e70737
   2021-05-30 14:44:06,657 [RatisPipelineUtilsThread - 0] INFO org.apache.hadoop.hdds.scm.pipeline.RatisPipelineProvider: Send pipeline:PipelineID=fa2906e2-d989-402f-8148-d9bef3ac5258 close command to datanode 0a16a9a7-1af0-4fbe-9b32-9e67df46b4c7
   2021-05-30 14:44:06,657 [RatisPipelineUtilsThread - 0] INFO org.apache.hadoop.hdds.scm.pipeline.RatisPipelineProvider: Send pipeline:PipelineID=fa2906e2-d989-402f-8148-d9bef3ac5258 close command to datanode 160ad09d-73b5-4392-b08b-3b93befd71d2
   2021-05-30 14:44:06,659 [9e77f811-8df6-4a59-9642-0f40d6f01764@group-58D600BFB107-StateMachineUpdater] INFO org.apache.hadoop.hdds.scm.pipeline.PipelineStateManager: Pipeline Pipeline[ Id: fa2906e2-d989-402f-8148-d9bef3ac5258, Nodes: 71935d59-fadc-4951-a08f-035450e70737{ip: 11.61.45.54, host: 11.61.45.54, ports: [REPLICATION=9886, RATIS=9858, RATIS_ADMIN=9858, RATIS_SERVER=9858, STANDALONE=9859], networkLocation: /rack582788, certSerialId: null, persistedOpState: IN_SERVICE, persistedOpStateExpiryEpochSec: 0}0a16a9a7-1af0-4fbe-9b32-9e67df46b4c7{ip: 11.26.17.139, host: 11.26.17.139, ports: [REPLICATION=9886, RATIS=9858, RATIS_ADMIN=9858, RATIS_SERVER=9858, STANDALONE=9859], networkLocation: /rack561349, certSerialId: null, persistedOpState: IN_SERVICE, persistedOpStateExpiryEpochSec: 0}160ad09d-73b5-4392-b08b-3b93befd71d2{ip: 11.61.45.51, host: 11.61.45.51, ports: [REPLICATION=9886, RATIS=9858, RATIS_ADMIN=9858, RATIS_SERVER=9858, STANDALONE=9859], networkLocation: /rack582788, cert
 SerialId: null, persistedOpState: IN_SERVICE, persistedOpStateExpiryEpochSec: 0}, Type:RATIS, Factor:THREE, State:CLOSED, leaderId:, CreationTimestamp2021-05-30T06:38:06.651Z] removed.
   
   
   3, when the second removePipeline is applied by SCMStateMachine, the PipelineNotFoundException crashed the SCM, and SCM refuses to start again.
   
   > 2021-05-30 14:44:06,659 [EventQueue-PipelineActionsForPipelineActionHandler] INFO org.apache.hadoop.hdds.scm.ha.SCMHAInvocationHandler: Invoking method public abstract void org.apache.hadoop.hdds.scm.pipeline.StateManager.removePipeline(org.apache.hadoop.hdds.protocol.proto.HddsProtos$PipelineID) throws java.io.IOException on target org.apache.hadoop.hdds.scm.ha.SCMRatisServerImpl@335aa187, cost 1709.382us
   2021-05-30 14:44:06,662 [9e77f811-8df6-4a59-9642-0f40d6f01764@group-58D600BFB107-StateMachineUpdater] ERROR org.apache.ratis.statemachine.StateMachine: Terminating with exit status 1: PipelineID=fa2906e2-d989-402f-8148-d9bef3ac5258 not found
   org.apache.hadoop.hdds.scm.pipeline.PipelineNotFoundException: PipelineID=fa2906e2-d989-402f-8148-d9bef3ac5258 not found
           at org.apache.hadoop.hdds.scm.pipeline.PipelineStateMap.getPipeline(PipelineStateMap.java:131)
           at org.apache.hadoop.hdds.scm.pipeline.PipelineStateMap.removePipeline(PipelineStateMap.java:343)
           at org.apache.hadoop.hdds.scm.pipeline.PipelineStateManagerV2Impl.removePipeline(PipelineStateManagerV2Impl.java:228)
           at sun.reflect.GeneratedMethodAccessor132.invoke(Unknown Source)
           at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
           at java.lang.reflect.Method.invoke(Method.java:498)
           at org.apache.hadoop.hdds.scm.ha.SCMStateMachine.process(SCMStateMachine.java:155)
           at org.apache.hadoop.hdds.scm.ha.SCMStateMachine.applyTransaction(SCMStateMachine.java:132)
           at org.apache.ratis.server.impl.RaftServerImpl.applyLogToStateMachine(RaftServerImpl.java:1661)
           at org.apache.ratis.server.impl.StateMachineUpdater.applyLog(StateMachineUpdater.java:234)
           at org.apache.ratis.server.impl.StateMachineUpdater.run(StateMachineUpdater.java:179)
           at java.lang.Thread.run(Thread.java:748)
   2021-05-30 14:44:06,664 [shutdown-hook-0] INFO org.apache.hadoop.hdds.scm.server.StorageContainerManagerStarter: SHUTDOWN_MSG: 
   /************************************************************
   SHUTDOWN_MSG: Shutting down StorageContainerManager at tdw-11-0-119-77/11.0.119.77
   ************************************************************/
   
   
   I was planing to create a jira for the contention issue, seems your guys meet it as well.


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[GitHub] [ozone] GlenGeng edited a comment on pull request #2295: HDDS-5284. [SCM-HA] SCM start failed with PipelineNotFoundException.

Posted by GitBox <gi...@apache.org>.
GlenGeng edited a comment on pull request #2295:
URL: https://github.com/apache/ozone/pull/2295#issuecomment-852861653


   `PipelineManager.closePipeline()` will be called from `DeadNodeHandler`, `StaleNodeHandler`, `PipelineActionHandler` from `EventHandler` and `PipelineManagerV2Impl.scrubPipeline()` from `BackgroundPipelineCreator`.
   
   `PipelineManager.closePipeline()` will call `stateManager.updatePipelineState()` and `stateManager.removePipeline()` sequentially. 
   
   Thread 1 and thread 2 calling `closePipeline` simultaneously is the root cause of the contention, and the consequence is PipelineNotFoundException.
   
   I haven't figured out a possible fix, since synchronizing on the pipeline object cannot solve the remove case.


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[GitHub] [ozone] GlenGeng commented on pull request #2295: HDDS-5284. [SCM-HA] SCM start failed with PipelineNotFoundException.

Posted by GitBox <gi...@apache.org>.
GlenGeng commented on pull request #2295:
URL: https://github.com/apache/ozone/pull/2295#issuecomment-852861653


   `PipelineManager.closePipeline()` will be called from `DeadNodeHandler`, `StaleNodeHandler`, `PipelineActionHandler` from `EventHandler` and `PipelineManagerV2Impl.scrubPipeline()` from `BackgroundPipelineCreator`.
   
   `PipelineManager.closePipeline()` will call `stateManager.updatePipelineState()` and `stateManager.removePipeline()` sequentially. 
   
   Thread 1 and thread 2 calling `closePipeline` simultaneously is the root cause of the contention, and the consequence is PipelineNotFoundException.
   
   I haven't figured out a possible fix, since synchronizing on the pipeline object cannot solve the remove case.


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[GitHub] [ozone] bshashikant merged pull request #2295: HDDS-5284. [SCM-HA] SCM start failed with PipelineNotFoundException.

Posted by GitBox <gi...@apache.org>.
bshashikant merged pull request #2295:
URL: https://github.com/apache/ozone/pull/2295


   


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[GitHub] [ozone] GlenGeng commented on pull request #2295: HDDS-5284. [SCM-HA] SCM start failed with PipelineNotFoundException.

Posted by GitBox <gi...@apache.org>.
GlenGeng commented on pull request #2295:
URL: https://github.com/apache/ozone/pull/2295#issuecomment-853546833






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[GitHub] [ozone] bshashikant commented on pull request #2295: HDDS-5284. [SCM-HA] SCM start failed with PipelineNotFoundException.

Posted by GitBox <gi...@apache.org>.
bshashikant commented on pull request #2295:
URL: https://github.com/apache/ozone/pull/2295#issuecomment-852853044


   > IMO current fix of ignoring PipelineNotFoundException in updatePipelineState() may not be able to thoroughly handle the contention between EventHandler (StaleNodeHandler, DeadNodeHandler, PipelineActionHandler) and BackgroundPipelineCreatorV2.
     @GlenGeng can you explain the problems and possible solutions to address the problem here in bit detail?
   


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[GitHub] [ozone] bharatviswa504 commented on a change in pull request #2295: HDDS-5284. [SCM-HA] SCM start failed with PipelineNotFoundException.

Posted by GitBox <gi...@apache.org>.
bharatviswa504 commented on a change in pull request #2295:
URL: https://github.com/apache/ozone/pull/2295#discussion_r642992339



##########
File path: hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/pipeline/PipelineStateManagerV2Impl.java
##########
@@ -256,6 +256,9 @@ public void updatePipelineState(
         transactionBuffer
             .addToBuffer(pipelineStore, pipelineID, getPipeline(pipelineID));
       }
+    } catch (PipelineNotFoundException pnfe) {
+      LOG.info("Pipeline {} is not found in the pipeline Map. Pipeline"

Review comment:
       Minor: can we make it warn?




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[GitHub] [ozone] GlenGeng commented on pull request #2295: HDDS-5284. [SCM-HA] SCM start failed with PipelineNotFoundException.

Posted by GitBox <gi...@apache.org>.
GlenGeng commented on pull request #2295:
URL: https://github.com/apache/ozone/pull/2295#issuecomment-853546833


   A naive and straightforward solution might be handle PipelineNotFoundException in both `stateManager.updatePipelineState` and `stateManager.removePipeline()`, since there will only be interleaved and sequential call sequence of the above two functions from StateMachineUpdater, 


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[GitHub] [ozone] GlenGeng commented on pull request #2295: HDDS-5284. [SCM-HA] SCM start failed with PipelineNotFoundException.

Posted by GitBox <gi...@apache.org>.
GlenGeng commented on pull request #2295:
URL: https://github.com/apache/ozone/pull/2295#issuecomment-854313457


   +1.
   
   Thanks @bshashikant for the fix, waiting for CI pass. AFAIK, this hot fix can solve the contention problem which is very critical for production env. Hope there can be a more decent solution for such issue in future.


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