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Hadoop QA commented on HDFS-8131: --------------------------------- \\ \\ | (/) *{color:green}+1 overall{color}* | \\ \\ || Vote || Subsystem || Runtime || Comment || | {color:blue}0{color} | pre-patch | 15m 8s | Pre-patch trunk compilation is healthy. | | {color:green}+1{color} | @author | 0m 0s | The patch does not contain any @author tags. | | {color:green}+1{color} | tests included | 0m 0s | The patch appears to include 1 new or modified test files. | | {color:green}+1{color} | javac | 7m 41s | There were no new javac warning messages. | | {color:green}+1{color} | javadoc | 9m 56s | There were no new javadoc warning messages. | | {color:green}+1{color} | release audit | 0m 23s | The applied patch does not increase the total number of release audit warnings. | | {color:green}+1{color} | checkstyle | 0m 38s | There were no new checkstyle issues. | | {color:green}+1{color} | whitespace | 0m 0s | The patch has no lines that end in whitespace. | | {color:green}+1{color} | install | 1m 40s | mvn install still works. | | {color:green}+1{color} | eclipse:eclipse | 0m 33s | The patch built with eclipse:eclipse. | | {color:green}+1{color} | findbugs | 3m 21s | The patch does not introduce any new Findbugs (version 3.0.0) warnings. | | {color:green}+1{color} | native | 3m 18s | Pre-build of native portion | | {color:green}+1{color} | hdfs tests | 167m 57s | Tests passed in hadoop-hdfs. | | | | 210m 38s | | \\ \\ || Subsystem || Report/Notes || | Patch URL | http://issues.apache.org/jira/secure/attachment/12733696/HDFS-8131.006.patch | | Optional Tests | javadoc javac unit findbugs checkstyle | | git revision | trunk / 0790275 | | hadoop-hdfs test log | https://builds.apache.org/job/PreCommit-HDFS-Build/11042/artifact/patchprocess/testrun_hadoop-hdfs.txt | | Test Results | https://builds.apache.org/job/PreCommit-HDFS-Build/11042/testReport/ | | Java | 1.7.0_55 | | uname | Linux asf904.gq1.ygridcore.net 3.13.0-36-lowlatency #63-Ubuntu SMP PREEMPT Wed Sep 3 21:56:12 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux | | Console output | https://builds.apache.org/job/PreCommit-HDFS-Build/11042/console | This message was automatically generated. > Implement a space balanced block placement policy > ------------------------------------------------- > > Key: HDFS-8131 > URL: https://issues.apache.org/jira/browse/HDFS-8131 > Project: Hadoop HDFS > Issue Type: Improvement > Components: namenode > Affects Versions: 3.0.0 > Reporter: Liu Shaohui > Assignee: Liu Shaohui > Priority: Minor > Labels: BlockPlacementPolicy > Attachments: HDFS-8131-v1.diff, HDFS-8131-v2.diff, HDFS-8131-v3.diff, > HDFS-8131.004.patch, HDFS-8131.005.patch, HDFS-8131.006.patch, balanced.png > > > The default block placement policy will choose datanodes for new blocks > randomly, which will result in unbalanced space used percent among datanodes > after an cluster expansion. The old datanodes always are in high used percent > of space and new added ones are in low percent. > Through we can used the external balance tool to balance the space used rate, > it will cost extra network IO and it's not easy to control the balance speed. > An easy solution is to implement an balanced block placement policy which > will choose low used percent datanodes for new blocks with a little high > possibility. In a not long term, the used percent of datanodes will trend to > be balanced. > Suggestions and discussions are welcomed. Thanks -- This message was sent by Atlassian JIRA (v6.3.4#6332)