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ASF GitHub Bot logged work on HDFS-16456: ----------------------------------------- Author: ASF GitHub Bot Created on: 26/May/22 23:38 Start Date: 26/May/22 23:38 Worklog Time Spent: 10m Work Description: hadoop-yetus commented on PR #4358: URL: https://github.com/apache/hadoop/pull/4358#issuecomment-1139145684 :broken_heart: **-1 overall** | Vote | Subsystem | Runtime | Logfile | Comment | |:----:|----------:|--------:|:--------:|:-------:| | +0 :ok: | reexec | 0m 52s | | Docker mode activated. | |||| _ Prechecks _ | | +1 :green_heart: | dupname | 0m 1s | | No case conflicting files found. | | +0 :ok: | codespell | 0m 0s | | codespell was not available. | | +0 :ok: | detsecrets | 0m 0s | | detect-secrets was not available. | | +1 :green_heart: | @author | 0m 0s | | The patch does not contain any @author tags. | | +1 :green_heart: | test4tests | 0m 0s | | The patch appears to include 2 new or modified test files. | |||| _ branch-3.2 Compile Tests _ | | +0 :ok: | mvndep | 4m 44s | | Maven dependency ordering for branch | | +1 :green_heart: | mvninstall | 27m 50s | | branch-3.2 passed | | +1 :green_heart: | compile | 16m 8s | | branch-3.2 passed | | +1 :green_heart: | checkstyle | 3m 11s | | branch-3.2 passed | | +1 :green_heart: | mvnsite | 3m 15s | | branch-3.2 passed | | +1 :green_heart: | javadoc | 2m 51s | | branch-3.2 passed | | +1 :green_heart: | spotbugs | 6m 4s | | branch-3.2 passed | | +1 :green_heart: | shadedclient | 18m 5s | | branch has no errors when building and testing our client artifacts. | |||| _ Patch Compile Tests _ | | +0 :ok: | mvndep | 0m 27s | | Maven dependency ordering for patch | | +1 :green_heart: | mvninstall | 2m 8s | | the patch passed | | +1 :green_heart: | compile | 15m 18s | | the patch passed | | +1 :green_heart: | javac | 15m 18s | | the patch passed | | +1 :green_heart: | blanks | 0m 0s | | The patch has no blanks issues. | | +1 :green_heart: | checkstyle | 3m 1s | | the patch passed | | +1 :green_heart: | mvnsite | 3m 13s | | the patch passed | | +1 :green_heart: | javadoc | 2m 43s | | the patch passed | | +1 :green_heart: | spotbugs | 6m 10s | | the patch passed | | +1 :green_heart: | shadedclient | 18m 13s | | patch has no errors when building and testing our client artifacts. | |||| _ Other Tests _ | | +1 :green_heart: | unit | 16m 30s | | hadoop-common in the patch passed. | | -1 :x: | unit | 212m 31s | [/patch-unit-hadoop-hdfs-project_hadoop-hdfs.txt](https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-4358/2/artifact/out/patch-unit-hadoop-hdfs-project_hadoop-hdfs.txt) | hadoop-hdfs in the patch passed. | | +1 :green_heart: | asflicense | 1m 23s | | The patch does not generate ASF License warnings. | | | | 363m 29s | | | | Reason | Tests | |-------:|:------| | Failed junit tests | hadoop.hdfs.tools.TestDFSZKFailoverController | | | hadoop.hdfs.TestDecommissionWithStriped | | Subsystem | Report/Notes | |----------:|:-------------| | Docker | ClientAPI=1.41 ServerAPI=1.41 base: https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-4358/2/artifact/out/Dockerfile | | GITHUB PR | https://github.com/apache/hadoop/pull/4358 | | Optional Tests | dupname asflicense compile javac javadoc mvninstall mvnsite unit shadedclient spotbugs checkstyle codespell detsecrets | | uname | Linux 3ff3eb2d0a7c 4.15.0-175-generic #184-Ubuntu SMP Thu Mar 24 17:48:36 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux | | Build tool | maven | | Personality | dev-support/bin/hadoop.sh | | git revision | branch-3.2 / 7ebbaa393860a115aa1f51edc02f640507ced9e0 | | Default Java | Private Build-1.8.0_312-8u312-b07-0ubuntu1~18.04-b07 | | Test Results | https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-4358/2/testReport/ | | Max. process+thread count | 1913 (vs. ulimit of 5500) | | modules | C: hadoop-common-project/hadoop-common hadoop-hdfs-project/hadoop-hdfs U: . | | Console output | https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-4358/2/console | | versions | git=2.17.1 maven=3.6.0 spotbugs=4.2.2 | | Powered by | Apache Yetus 0.14.0 https://yetus.apache.org | This message was automatically generated. Issue Time Tracking ------------------- Worklog Id: (was: 775293) Time Spent: 3h 20m (was: 3h 10m) > EC: Decommission a rack with only on dn will fail when the rack number is > equal with replication > ------------------------------------------------------------------------------------------------ > > Key: HDFS-16456 > URL: https://issues.apache.org/jira/browse/HDFS-16456 > Project: Hadoop HDFS > Issue Type: Bug > Components: ec, namenode > Affects Versions: 3.4.0 > Reporter: caozhiqiang > Assignee: caozhiqiang > Priority: Critical > Labels: pull-request-available > Fix For: 3.4.0, 3.3.4 > > Attachments: HDFS-16456.001.patch, HDFS-16456.002.patch, > HDFS-16456.003.patch, HDFS-16456.004.patch, HDFS-16456.005.patch, > HDFS-16456.006.patch, HDFS-16456.007.patch, HDFS-16456.008.patch, > HDFS-16456.009.patch, HDFS-16456.010.patch > > Time Spent: 3h 20m > Remaining Estimate: 0h > > In below scenario, decommission will fail by TOO_MANY_NODES_ON_RACK reason: > # Enable EC policy, such as RS-6-3-1024k. > # The rack number in this cluster is equal with or less than the replication > number(9) > # A rack only has one DN, and decommission this DN. > The root cause is in > BlockPlacementPolicyRackFaultTolerant::getMaxNodesPerRack() function, it will > give a limit parameter maxNodesPerRack for choose targets. In this scenario, > the maxNodesPerRack is 1, which means each rack can only be chosen one > datanode. > {code:java} > protected int[] getMaxNodesPerRack(int numOfChosen, int numOfReplicas) { > ... > // If more replicas than racks, evenly spread the replicas. > // This calculation rounds up. > int maxNodesPerRack = (totalNumOfReplicas - 1) / numOfRacks + 1; > return new int[] {numOfReplicas, maxNodesPerRack}; > } {code} > int maxNodesPerRack = (totalNumOfReplicas - 1) / numOfRacks + 1; > here will be called, where totalNumOfReplicas=9 and numOfRacks=9 > When we decommission one dn which is only one node in its rack, the > chooseOnce() in BlockPlacementPolicyRackFaultTolerant::chooseTargetInOrder() > will throw NotEnoughReplicasException, but the exception will not be caught > and fail to fallback to chooseEvenlyFromRemainingRacks() function. > When decommission, after choose targets, verifyBlockPlacement() function will > return the total rack number contains the invalid rack, and > BlockPlacementStatusDefault::isPlacementPolicySatisfied() will return false > and it will also cause decommission fail. > {code:java} > public BlockPlacementStatus verifyBlockPlacement(DatanodeInfo[] locs, > int numberOfReplicas) { > if (locs == null) > locs = DatanodeDescriptor.EMPTY_ARRAY; > if (!clusterMap.hasClusterEverBeenMultiRack()) { > // only one rack > return new BlockPlacementStatusDefault(1, 1, 1); > } > // Count locations on different racks. > Set<String> racks = new HashSet<>(); > for (DatanodeInfo dn : locs) { > racks.add(dn.getNetworkLocation()); > } > return new BlockPlacementStatusDefault(racks.size(), numberOfReplicas, > clusterMap.getNumOfRacks()); > } {code} > {code:java} > public boolean isPlacementPolicySatisfied() { > return requiredRacks <= currentRacks || currentRacks >= totalRacks; > }{code} > According to the above description, we should make the below modify to fix it: > # In startDecommission() or stopDecommission(), we should also change the > numOfRacks in class NetworkTopology. Or choose targets may fail for the > maxNodesPerRack is too small. And even choose targets success, > isPlacementPolicySatisfied will also return false cause decommission fail. > # In BlockPlacementPolicyRackFaultTolerant::chooseTargetInOrder(), the first > chooseOnce() function should also be put in try..catch..., or it will not > fallback to call chooseEvenlyFromRemainingRacks() when throw exception. > # In verifyBlockPlacement, we need to remove invalid racks from total > numOfRacks, or isPlacementPolicySatisfied() will return false and cause fail > to reconstruct data. > > -- This message was sent by Atlassian Jira (v8.20.7#820007) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org