HDDS-4404. Datanode can go OOM when a Recon or SCM Server is very slow in processing reports #1601

smengcl · 2020-11-19T00:58:54Z

This is an improved version of the previous fix (#1552) for HDDS-4404.

The approach is relatively straightforward: DN will only save the latest containerReport/nodeReport/pipelineReport in StateContext (instead of the previous behavior where DN keeps putting all reports back on communication error.)

Testing

Existing tests in TestHeartbeatEndpointTask passed locally.
New UTs added.
Internal scale test w/ 1M containers passed: recon unresponsive for 48 hours, DN heap usage kept at the same level -- w/o patch the DNs OOM'ed after 24 hours (All 15 DNs max heap set to 32GB, reports queue kept growing).

…w in processing reports. Change-Id: Idf6394d0bde2fb1c9fe99a96c49fa28677e0e527

avijayanhwx

@smengcl Thanks for working on this. Approach looks good to me.

Can we add a unit test to make sure the basic works? (addReport updates the report, and subsequent getReports should get the newly added report)

...ervice/src/main/java/org/apache/hadoop/ozone/container/common/statemachine/StateContext.java

...ain/java/org/apache/hadoop/ozone/container/common/states/endpoint/HeartbeatEndpointTask.java

Change-Id: I6c4729634905bf6bba5bb6483c393d3c7511a78e

smengcl · 2020-11-19T20:03:03Z

UT TestStateContext#testReportAPIs is not happy with my change in StateContext#addReport:

ozone/hadoop-hdds/container-service/src/test/java/org/apache/hadoop/ozone/container/common/statemachine/TestStateContext.java

Line 68 in a4f7e32

stateContext.addReport(mock(GeneratedMessage.class));

Mocked object GeneratedMessage report is fed to addReport(), so report.getDescriptorForType() returns null. As a result report.getDescriptorForType().getFullName() throws NPE in the UT.

Change-Id: I63470510ed2089438f08f4d3cea321c1b5f01c3c

Change-Id: Id3ff6222ed279568d32876afc0a6a5ee1316c926

Change-Id: I25020b4411f4163a2ec134431793bfe663e5f6bf

Change-Id: I2dc93c42fc7468b37d41a179ca047ee385fc8896

GlenGeng-awx · 2020-11-20T06:42:36Z

...ervice/src/main/java/org/apache/hadoop/ozone/container/common/statemachine/StateContext.java

+      final String reportType = report.getDescriptorForType().getFullName();
+      for (InetSocketAddress endpoint : endpoints) {
+        // We only keep the latest container, node and pipeline report
+        if (reportType.equals(CONTAINER_REPORTS_PROTO_NAME)) {


Do we need to synchronize the get/set on these containerReport/nodeReport/pipelineReport ?

No, container/node/pipeline should be fine. We need synchroized on reports because we want Map get and add not to get messed in between.

one thread write containerReport and another thread read containerReport, it's not thread safe, we can use AtomicReference<GeneratedMessage> containerReports

…d by adding mock-maker-inline. Change-Id: I0f21c508af1f7b36d7632aaa3b9173a17056f211

Change-Id: I8d67a1b6e2d9043fb1479e2547d2e690932f7985

Change-Id: Iaec544ba6fb211d0d71fe03b26b0fc70199dc882

...ervice/src/main/java/org/apache/hadoop/ozone/container/common/statemachine/StateContext.java

runzhiwang · 2020-11-23T06:32:53Z

@smengcl Thanks the patch. It looks good to me overall. But I think we need more strong integration test to cover the case: StateContext#reports will not contain any ContainerReport, NodeReport, and DatanodeReport.

…e only used in UT, at least at the moment. Change-Id: I72070fde8df220ecebf2fb6d1015d19f65cee11e

smengcl · 2020-11-23T06:43:01Z

@smengcl Thanks the patch. It looks good to me overall. But I think we need more strong integration test to cover the case: StateContext#reports will not contain any ContainerReport, NodeReport, and DatanodeReport.

Thanks for the review @runzhiwang . In a previous revision I had a strict check in StateContext#addReport:
22846f4#diff-4e474a0cbb28091ed4fab8ee80878c3acf7e15711fba2a0d83bacd56ea8f5707L237-L240

which ensures only CommandStatusReports and IncrementalContainerReport would ever be added to reports queue. Later this is removed since @avijayanhwx suggested we don't really need that.

The only two paths where reports would be queued are addReports and StateContext#putBackReports, where HeartbeatEndpointTask#putBackReports makes sure we only put back CommandStatusReports and IncrementalContainerReport.

Would you elaborate on the integration test plan you have on your mind?

runzhiwang · 2020-11-23T07:11:57Z

Thanks for the review @runzhiwang . In a previous revision I had a strict check in StateContext#addReport:
22846f4#diff-4e474a0cbb28091ed4fab8ee80878c3acf7e15711fba2a0d83bacd56ea8f5707L237-L240

which ensures only CommandStatusReports and IncrementalContainerReport would ever be added to reports queue. Later this is removed since @avijayanhwx suggested we don't really need that.

The only two paths where reports would be queued are addReports and StateContext#putBackReports, where HeartbeatEndpointTask#putBackReports makes sure we only put back CommandStatusReports and IncrementalContainerReport.

Would you elaborate on the integration test plan you have on your mind?

@smengcl OOM is a serious problem, so we need strong test. If somebody change the existed two path, or add the third path, and put ContainerReport in the queue, OOM will happen, so we need some restrain. The integration test maybe only can cover the existed two path, for example, you can decrease the time interval of ReportPublisher#call and increase the time interval of EndpointStateMachine.EndPointStates call(), so that ContainerReport generated many times but has not been send out, then we check the reports do not contain ContainerReport.

smengcl

Thanks for the review @runzhiwang . In a previous revision I had a strict check in StateContext#addReport:
22846f4#diff-4e474a0cbb28091ed4fab8ee80878c3acf7e15711fba2a0d83bacd56ea8f5707L237-L240
which ensures only CommandStatusReports and IncrementalContainerReport would ever be added to reports queue. Later this is removed since @avijayanhwx suggested we don't really need that.
The only two paths where reports would be queued are addReports and StateContext#putBackReports, where HeartbeatEndpointTask#putBackReports makes sure we only put back CommandStatusReports and IncrementalContainerReport.
Would you elaborate on the integration test plan you have on your mind?

@smengcl OOM is a serious problem, so we need strong test. If somebody change the existed two path, or add the third path, and put ContainerReport in the queue, OOM will happen, so we need some restrain. The integration test maybe only can cover the existed two path, for example, you can decrease the time interval of ReportPublisher#call and increase the time interval of EndpointStateMachine.EndPointStates call(), so that ContainerReport generated many times but has not been send out, then we check the reports do not contain ContainerReport.

Thanks @runzhiwang .

I think a better and easier way to check this behavior is to add a new UT that calls addReports and putBackReports repetitively, then check the reports queue length. Should only expect the queue grow when report type is CommandStatusReport or IncrementalContainerReport, but not any other ones. What do you think?

…e functionality of the map. - Added `acceptedIncrementalReportTypeSet` for rigorous report type checking. - `StateContext#addReport` now explicitly throws, instead of hiding any possible NPEs. Rationale: As I think again, those reports are all internally generated rather than dependent on direct user input. It's better to catch any problem early (if any). - `StateContext#addReport` also strictly checks for report type now. This intends to force any future additions of report types to be explicitly allowed. Only 5 report types (names) are expected: ``` hadoop.hdds.NodeReportProto hadoop.hdds.ContainerReportsProto hadoop.hdds.IncrementalContainerReportProto hadoop.hdds.CommandStatusReportsProto hadoop.hdds.PipelineReportsProto ``` - `StateContext#putBackReports` now checks ALL reports in the list to be put back. I'd expect the list to be small. And since the logic is run on each DataNode, it shouldn't become a performance bottleneck. Also added debug logging just in case we need to diagnose it in the future. - Added new UT `testPutBackReports` and `testReportQueueWithAddReports` to check that `putBackReports` and `getReports` behaves. Change-Id: I48aca3d4a422d52532b39c9462a30519c9cbe0eb

smengcl · 2020-11-24T07:00:17Z

Summary of major changes to the latest diff:

Renamed reports to incrementalReportsQueue to better reflect the functionality of the map.
Added acceptedIncrementalReportTypeSet for rigorous report type checking.
StateContext#addReport now explicitly throws, instead of hiding any possible NPEs. Rationale: As I think again, those reports are all internally generated rather than dependent on direct user input. It's better to catch any problem early (if any).
StateContext#addReport also strictly checks for report type now. This intends to force any future additions of report types to be explicitly allowed. Only 5 report types (names) are expected:

hadoop.hdds.NodeReportProto
hadoop.hdds.ContainerReportsProto
hadoop.hdds.IncrementalContainerReportProto
hadoop.hdds.CommandStatusReportsProto
hadoop.hdds.PipelineReportsProto

StateContext#putBackReports now checks ALL reports in the list to be put back. I'd expect the list to be small. And since the logic is run on each DataNode, it shouldn't become a performance bottleneck. Also added debug logging just in case we need to diagnose it in the future.
Added new UT testPutBackReports and testReportQueueWithAddReports to check that putBackReports and getReports behaves.

Let me know if you think I missed anything, or it might be a bit over overkill.

runzhiwang · 2020-11-24T07:02:40Z

Thanks for the review @runzhiwang . In a previous revision I had a strict check in StateContext#addReport:
22846f4#diff-4e474a0cbb28091ed4fab8ee80878c3acf7e15711fba2a0d83bacd56ea8f5707L237-L240
which ensures only CommandStatusReports and IncrementalContainerReport would ever be added to reports queue. Later this is removed since @avijayanhwx suggested we don't really need that.
The only two paths where reports would be queued are addReports and StateContext#putBackReports, where HeartbeatEndpointTask#putBackReports makes sure we only put back CommandStatusReports and IncrementalContainerReport.
Would you elaborate on the integration test plan you have on your mind?

@smengcl OOM is a serious problem, so we need strong test. If somebody change the existed two path, or add the third path, and put ContainerReport in the queue, OOM will happen, so we need some restrain. The integration test maybe only can cover the existed two path, for example, you can decrease the time interval of ReportPublisher#call and increase the time interval of EndpointStateMachine.EndPointStates call(), so that ContainerReport generated many times but has not been send out, then we check the reports do not contain ContainerReport.

Thanks @runzhiwang .

I think a better and easier way to check this behavior is to add a new UT that calls addReports and putBackReports repetitively, then check the reports queue length. Should only expect the queue grow when report type is CommandStatusReport or IncrementalContainerReport, but not any other ones. What do you think?

@smengcl I agree.

Change-Id: I44aba0ff093fa0ff5f9a35a74ff4126d9c73dd7b

Change-Id: I545ca8c636b8bbd1239a936603b6efcbfbd10b88

Change-Id: I5cdc38a297cf3d91bad8335eb36f2ba6b2009c10

GlenGeng-awx · 2020-11-24T07:33:32Z

...ervice/src/main/java/org/apache/hadoop/ozone/container/common/statemachine/StateContext.java

  private final Set<InetSocketAddress> endpoints;
-  private final Map<InetSocketAddress, List<GeneratedMessage>> reports;
+  // Only the latest full report of each type is kept
+  private final AtomicReference<GeneratedMessage> containerReports;


You may make them to be volatile, which is simpler but thread safe as well,

Thanks for the tip. I will keep atomic for now as the report is not updated so frequently on DNs (low performance impact).

…ntainer/Node/Pipeline reports. Thanks Aravindan. Change-Id: Ic39f53de8bb91a179bd5dc3301aa89ffecf5c076

runzhiwang

+1

runzhiwang · 2020-11-30T23:36:56Z

Reopen pr to trigger CI

runzhiwang · 2020-12-01T09:23:38Z

Waiting CI pass.

avijayanhwx

Thanks for working on this @smengcl. LGTM +1 pending CI.

smengcl · 2020-12-01T19:23:01Z

Thanks @runzhiwang @avijayanhwx @GlenGeng for the review and comments.

CI still has unrelated failures (TestOzoneManagerHAWithData#testOMRestart and acceptance.ozone-om-ha-s3). I will retrigger one more time.

Change-Id: I46fb65ce2c81cb607dd10a9ee829d829ec7a8cfc

Change-Id: I9d3b5ce0b81d457344ecd6b4ad6e141169bd89d3

Change-Id: I4e9dace08152e21c2bb5da564487d776a84c4ade

Change-Id: Iea89129865df35ca54d85307bac49ede5da45ea7

…stStorageContainerManager#testBlockDeletionTransactions. Change-Id: I16c8bfcfbd619a23241ea6dda9b95265714984bb

smengcl · 2020-12-09T17:49:13Z

TestStorageContainerManager#testBlockDeletionTransactions was failing for a legitimate reason.
The small issue is addressed by simply returning (instead of throwing) when null is passed into StateContext#addReport.

Change-Id: I64203ebbaeebdb4c598bb8dad578579c82bf604b

smengcl · 2020-12-10T19:25:33Z

TestDecommissionAndMaintenance#testNodeWithOpenPipelineCanBeDecommissioned passed locally for me. Retriggering CI.

runzhiwang · 2020-12-14T11:30:06Z

@smengcl Thanks the patch. @adoroszlai @avijayanhwx @GlenGeng Thanks for review, I have merged the patch.

@VisibleForTesting

…w in processing reports (apache#1601) * HDDS-4404. Datanode can go OOM when a Recon or SCM Server is very slow in processing reports. Change-Id: Idf6394d0bde2fb1c9fe99a96c49fa28677e0e527 * Checkstyle. Change-Id: I6c4729634905bf6bba5bb6483c393d3c7511a78e * Add mock-maker-inline so UT can mock final classes. Change-Id: I63470510ed2089438f08f4d3cea321c1b5f01c3c * Remove throw exception in addReport. Change-Id: Id3ff6222ed279568d32876afc0a6a5ee1316c926 * Fix existing UT TestStateContext#testReportAPIs. Change-Id: I25020b4411f4163a2ec134431793bfe663e5f6bf * Remove unused imports. Change-Id: I2dc93c42fc7468b37d41a179ca047ee385fc8896 * Work around mockito bug in UT TestCreatePipelineCommandHandler: caused by adding mock-maker-inline. Change-Id: I0f21c508af1f7b36d7632aaa3b9173a17056f211 * Add UT testContainerNodePipelineReportAPIs. Change-Id: I8d67a1b6e2d9043fb1479e2547d2e690932f7985 * Clean up. Change-Id: Iaec544ba6fb211d0d71fe03b26b0fc70199dc882 * @VisibleForTesting for get container/node/pipeline reports as they are only used in UT, at least at the moment. Change-Id: I72070fde8df220ecebf2fb6d1015d19f65cee11e * - Renamed `reports` to `incrementalReportsQueue` to better reflect the functionality of the map. - Added `acceptedIncrementalReportTypeSet` for rigorous report type checking. - `StateContext#addReport` now explicitly throws, instead of hiding any possible NPEs. Rationale: As I think again, those reports are all internally generated rather than dependent on direct user input. It's better to catch any problem early (if any). - `StateContext#addReport` also strictly checks for report type now. This intends to force any future additions of report types to be explicitly allowed. Only 5 report types (names) are expected: ``` hadoop.hdds.NodeReportProto hadoop.hdds.ContainerReportsProto hadoop.hdds.IncrementalContainerReportProto hadoop.hdds.CommandStatusReportsProto hadoop.hdds.PipelineReportsProto ``` - `StateContext#putBackReports` now checks ALL reports in the list to be put back. I'd expect the list to be small. And since the logic is run on each DataNode, it shouldn't become a performance bottleneck. Also added debug logging just in case we need to diagnose it in the future. - Added new UT `testPutBackReports` and `testReportQueueWithAddReports` to check that `putBackReports` and `getReports` behaves. Change-Id: I48aca3d4a422d52532b39c9462a30519c9cbe0eb * Make containerReports, nodeReport, pipelineReports atomic and final. Change-Id: I44aba0ff093fa0ff5f9a35a74ff4126d9c73dd7b * Checkstyle. Change-Id: I545ca8c636b8bbd1239a936603b6efcbfbd10b88 * Clean up. Change-Id: I5cdc38a297cf3d91bad8335eb36f2ba6b2009c10 * Remove assertion in putBackReports as requestBuilder might include Container/Node/Pipeline reports. Thanks Aravindan. Change-Id: Ic39f53de8bb91a179bd5dc3301aa89ffecf5c076 * Empty commit to retrigger CI. Change-Id: I46fb65ce2c81cb607dd10a9ee829d829ec7a8cfc * Empty commit to retrigger CI. Change-Id: I9d3b5ce0b81d457344ecd6b4ad6e141169bd89d3 * Retrigger. Change-Id: I4e9dace08152e21c2bb5da564487d776a84c4ade * Allow null as input to StateContext#addReport() as this blocked UT TestStorageContainerManager#testBlockDeletionTransactions. Change-Id: I16c8bfcfbd619a23241ea6dda9b95265714984bb * Retrigger CI Change-Id: I64203ebbaeebdb4c598bb8dad578579c82bf604b * trigger new CI check Co-authored-by: Doroszlai, Attila <[email protected]> (cherry picked from commit 0152eb5)

HDDS-4404. Datanode can go OOM when a Recon or SCM Server is very slo…

2cb1635

…w in processing reports. Change-Id: Idf6394d0bde2fb1c9fe99a96c49fa28677e0e527

smengcl added the datanode label Nov 19, 2020

smengcl requested review from avijayanhwx and nandakumar131 November 19, 2020 00:58

smengcl self-assigned this Nov 19, 2020

avijayanhwx reviewed Nov 19, 2020

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...ervice/src/main/java/org/apache/hadoop/ozone/container/common/statemachine/StateContext.java Outdated Show resolved Hide resolved

...ain/java/org/apache/hadoop/ozone/container/common/states/endpoint/HeartbeatEndpointTask.java Show resolved Hide resolved

Checkstyle.

3e53bf8

Change-Id: I6c4729634905bf6bba5bb6483c393d3c7511a78e

smengcl added 4 commits November 19, 2020 15:07

Add mock-maker-inline so UT can mock final classes.

024a4f8

Change-Id: I63470510ed2089438f08f4d3cea321c1b5f01c3c

Remove throw exception in addReport.

22846f4

Change-Id: Id3ff6222ed279568d32876afc0a6a5ee1316c926

Fix existing UT TestStateContext#testReportAPIs.

878d271

Change-Id: I25020b4411f4163a2ec134431793bfe663e5f6bf

Remove unused imports.

5b2bbd3

Change-Id: I2dc93c42fc7468b37d41a179ca047ee385fc8896

smengcl mentioned this pull request Nov 19, 2020

HDDS-4404. Datanode can go OOM when a Recon or SCM Server is very slow in processing reports #1552

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GlenGeng-awx reviewed Nov 20, 2020

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smengcl added 3 commits November 20, 2020 02:48

Work around mockito bug in UT TestCreatePipelineCommandHandler: cause…

2fcb2b6

…d by adding mock-maker-inline. Change-Id: I0f21c508af1f7b36d7632aaa3b9173a17056f211

Add UT testContainerNodePipelineReportAPIs.

c403208

Change-Id: I8d67a1b6e2d9043fb1479e2547d2e690932f7985

Clean up.

23d25cb

Change-Id: Iaec544ba6fb211d0d71fe03b26b0fc70199dc882

runzhiwang reviewed Nov 23, 2020

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...ervice/src/main/java/org/apache/hadoop/ozone/container/common/statemachine/StateContext.java Show resolved Hide resolved

@VisibleForTesting for get container/node/pipeline reports as they ar…

50b9a5e

…e only used in UT, at least at the moment. Change-Id: I72070fde8df220ecebf2fb6d1015d19f65cee11e

smengcl commented Nov 24, 2020

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smengcl added 3 commits November 23, 2020 23:06

Make containerReports, nodeReport, pipelineReports atomic and final.

9718488

Change-Id: I44aba0ff093fa0ff5f9a35a74ff4126d9c73dd7b

Checkstyle.

7988203

Change-Id: I545ca8c636b8bbd1239a936603b6efcbfbd10b88

Clean up.

fdc5823

Change-Id: I5cdc38a297cf3d91bad8335eb36f2ba6b2009c10

GlenGeng-awx reviewed Nov 24, 2020

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Remove assertion in putBackReports as requestBuilder might include Co…

3a32e8b

…ntainer/Node/Pipeline reports. Thanks Aravindan. Change-Id: Ic39f53de8bb91a179bd5dc3301aa89ffecf5c076

runzhiwang approved these changes Nov 30, 2020

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runzhiwang reopened this Nov 30, 2020

runzhiwang closed this Dec 1, 2020

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runzhiwang closed this Dec 1, 2020

runzhiwang reopened this Dec 1, 2020

avijayanhwx approved these changes Dec 1, 2020

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smengcl added 5 commits December 1, 2020 11:31

Empty commit to retrigger CI.

84e8f74

Change-Id: I46fb65ce2c81cb607dd10a9ee829d829ec7a8cfc

Empty commit to retrigger CI.

02298d9

Change-Id: I9d3b5ce0b81d457344ecd6b4ad6e141169bd89d3

Retrigger.

63a89ab

Change-Id: I4e9dace08152e21c2bb5da564487d776a84c4ade

Merge branch 'master' into HDDS-4404-v2

c64f247

Change-Id: Iea89129865df35ca54d85307bac49ede5da45ea7

Allow null as input to StateContext#addReport() as this blocked UT Te…

34283ca

…stStorageContainerManager#testBlockDeletionTransactions. Change-Id: I16c8bfcfbd619a23241ea6dda9b95265714984bb

Retrigger CI

ab37c22

Change-Id: I64203ebbaeebdb4c598bb8dad578579c82bf604b

trigger new CI check

f0dca47

runzhiwang merged commit 0152eb5 into apache:master Dec 14, 2020

HDDS-4404. Datanode can go OOM when a Recon or SCM Server is very slow in processing reports #1601

HDDS-4404. Datanode can go OOM when a Recon or SCM Server is very slow in processing reports #1601

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