[jira] [Comment Edited] (HDFS-12725) BlockPlacementPolicyRackFaultTolerant still fails with racks with very few nodes
[ https://issues.apache.org/jira/browse/HDFS-12725?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16221224#comment-16221224 ] Xiao Chen edited comment on HDFS-12725 at 10/26/17 8:54 PM: Patch 1 to reproduce the error and fix. This keeps the {{getMaxNodesPerRack}} calculation so normal placements can still be as even as possible. Modified unit test fail-before-pass-after. In real clusters this come in the form of message {{Cannot allocate parity block}} in the client and {{org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicy: Failed to place enough replicas, still in need of 3 to reach 14}} in the NN. [~andrew.wang] and [~eddyxu], could you take a look? was (Author: xiaochen): Patch 1 to reproduce the error and fix. [~andrew.wang] and [~eddyxu], could you take a look? > BlockPlacementPolicyRackFaultTolerant still fails with racks with very few > nodes > > > Key: HDFS-12725 > URL: https://issues.apache.org/jira/browse/HDFS-12725 > Project: Hadoop HDFS > Issue Type: Bug > Components: erasure-coding >Affects Versions: 3.0.0 >Reporter: Xiao Chen >Assignee: Xiao Chen > Attachments: HDFS-12725.01.patch, HDFS-12725.01.patch > > > HDFS-12567 tries to fix the scenario where EC blocks may not be allocated in > extremely rack-imbalanced cluster. > The added fall-back step of the fix could be improved to do a best-effort > placement. This is more likely to happen in testing than in real clusters. -- This message was sent by Atlassian JIRA (v6.4.14#64029) - To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org
[jira] [Comment Edited] (HDFS-12725) BlockPlacementPolicyRackFaultTolerant still fails with racks with very few nodes
[ https://issues.apache.org/jira/browse/HDFS-12725?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16225679#comment-16225679 ] Wei-Chiu Chuang edited comment on HDFS-12725 at 10/30/17 9:23 PM: -- Hi [~xiaochen] thanks for filing the jira and posting a patch. It might make the code more readable if you can refactor the catch block into a separate method, since that catch block is pretty long. A little nit in the debug message: {code} LOG.debug("Best effort placement failed."); {code} It might also be useful to log numResultsOflastChoose and totalReplicaExpected. One question regarding the test code: {code} for (int i = 0; i <= numSingleDnRacks; i++) { racks[i] = "/rack" + i; } for (int i = numSingleDnRacks + 1; i < numDatanodes; i++) { racks[i] = "/rack" + (numSingleDnRacks + (i % ( numRacks - numSingleDnRacks))); } {code} Can you explain why the first loop is between 0 <= i <= numSingleDnRacks? Why isn't it between 0 <= i BlockPlacementPolicyRackFaultTolerant still fails with racks with very few > nodes > > > Key: HDFS-12725 > URL: https://issues.apache.org/jira/browse/HDFS-12725 > Project: Hadoop HDFS > Issue Type: Bug > Components: erasure-coding >Affects Versions: 3.0.0 >Reporter: Xiao Chen >Assignee: Xiao Chen > Labels: hdfs-ec-3.0-must-do > Attachments: HDFS-12725.01.patch, HDFS-12725.02.patch > > > HDFS-12567 tries to fix the scenario where EC blocks may not be allocated in > extremely rack-imbalanced cluster. > The added fall-back step of the fix could be improved to do a best-effort > placement. This is more likely to happen in testing than in real clusters. -- This message was sent by Atlassian JIRA (v6.4.14#64029) - To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org
[jira] [Comment Edited] (HDFS-12725) BlockPlacementPolicyRackFaultTolerant still fails with racks with very few nodes
[ https://issues.apache.org/jira/browse/HDFS-12725?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16236556#comment-16236556 ] Lei (Eddy) Xu edited comment on HDFS-12725 at 11/2/17 8:42 PM: --- LGTM +1 pending the following comment: {noformat} " (maxNodesPerRack={}, numOfReplicas={}) nodes " + 144 "evenly across racks, falling back to uneven placement. {noformat} It should be something like "falling back to evenly placement on remained racks" Thanks Xiao. Btw, please verify that the test failures. was (Author: eddyxu): LGTM +1 pending the following comment: {preformat} " (maxNodesPerRack={}, numOfReplicas={}) nodes " + 144 "evenly across racks, falling back to uneven placement. {preformat} It should be something like "falling back to evenly placement on remained racks" Thanks Xiao. Btw, please verify that the test failures. > BlockPlacementPolicyRackFaultTolerant still fails with racks with very few > nodes > > > Key: HDFS-12725 > URL: https://issues.apache.org/jira/browse/HDFS-12725 > Project: Hadoop HDFS > Issue Type: Bug > Components: erasure-coding >Affects Versions: 3.0.0 >Reporter: Xiao Chen >Assignee: Xiao Chen >Priority: Major > Labels: hdfs-ec-3.0-must-do > Attachments: HDFS-12725.01.patch, HDFS-12725.02.patch, > HDFS-12725.03.patch, HDFS-12725.04.patch, HDFS-12725.05.patch > > > HDFS-12567 tries to fix the scenario where EC blocks may not be allocated in > extremely rack-imbalanced cluster. > The added fall-back step of the fix could be improved to do a best-effort > placement. This is more likely to happen in testing than in real clusters. -- This message was sent by Atlassian JIRA (v6.4.14#64029) - To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org