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Hadoop QA commented on HDFS-9092: --------------------------------- \\ \\ | (x) *{color:red}-1 overall{color}* | \\ \\ || Vote || Subsystem || Runtime || Comment || | {color:red}-1{color} | pre-patch | 18m 38s | Pre-patch trunk has 1 extant Findbugs (version 3.0.0) warnings. | | {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 57s | There were no new javac warning messages. | | {color:green}+1{color} | javadoc | 10m 23s | There were no new javadoc warning messages. | | {color:red}-1{color} | release audit | 0m 20s | The applied patch generated 1 release audit warnings. | | {color:green}+1{color} | checkstyle | 1m 47s | There were no new checkstyle issues. | | {color:red}-1{color} | whitespace | 0m 1s | The patch has 3 line(s) that end in whitespace. Use git apply --whitespace=fix. | | {color:green}+1{color} | install | 1m 30s | mvn install still works. | | {color:green}+1{color} | eclipse:eclipse | 0m 34s | The patch built with eclipse:eclipse. | | {color:red}-1{color} | findbugs | 3m 23s | The patch appears to introduce 2 new Findbugs (version 3.0.0) warnings. | | {color:green}+1{color} | native | 3m 13s | Pre-build of native portion | | {color:red}-1{color} | hdfs tests | 162m 40s | Tests failed in hadoop-hdfs. | | {color:green}+1{color} | hdfs tests | 1m 47s | Tests passed in hadoop-hdfs-nfs. | | | | 212m 19s | | \\ \\ || Reason || Tests || | FindBugs | module:hadoop-hdfs-nfs | | Failed unit tests | hadoop.hdfs.server.namenode.TestStartupProgressServlet | | | hadoop.hdfs.server.namenode.TestFileTruncate | | | hadoop.hdfs.tools.TestDFSAdminWithHA | | | hadoop.hdfs.web.TestWebHDFSOAuth2 | | | hadoop.hdfs.server.namenode.TestCacheDirectives | \\ \\ || Subsystem || Report/Notes || | Patch URL | http://issues.apache.org/jira/secure/attachment/12764084/HDFS-9092.002.patch | | Optional Tests | javadoc javac unit findbugs checkstyle | | git revision | trunk / e5992ef | | Pre-patch Findbugs warnings | https://builds.apache.org/job/PreCommit-HDFS-Build/12719/artifact/patchprocess/trunkFindbugsWarningshadoop-hdfs.html | | Release Audit | https://builds.apache.org/job/PreCommit-HDFS-Build/12719/artifact/patchprocess/patchReleaseAuditProblems.txt | | whitespace | https://builds.apache.org/job/PreCommit-HDFS-Build/12719/artifact/patchprocess/whitespace.txt | | Findbugs warnings | https://builds.apache.org/job/PreCommit-HDFS-Build/12719/artifact/patchprocess/newPatchFindbugsWarningshadoop-hdfs-nfs.html | | hadoop-hdfs test log | https://builds.apache.org/job/PreCommit-HDFS-Build/12719/artifact/patchprocess/testrun_hadoop-hdfs.txt | | hadoop-hdfs-nfs test log | https://builds.apache.org/job/PreCommit-HDFS-Build/12719/artifact/patchprocess/testrun_hadoop-hdfs-nfs.txt | | Test Results | https://builds.apache.org/job/PreCommit-HDFS-Build/12719/testReport/ | | Java | 1.7.0_55 | | uname | Linux asf900.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/12719/console | This message was automatically generated. > Nfs silently drops overlapping write requests and causes data copying to fail > ----------------------------------------------------------------------------- > > Key: HDFS-9092 > URL: https://issues.apache.org/jira/browse/HDFS-9092 > Project: Hadoop HDFS > Issue Type: Bug > Components: nfs > Affects Versions: 2.7.1 > Reporter: Yongjun Zhang > Assignee: Yongjun Zhang > Attachments: HDFS-9092.001.patch, HDFS-9092.002.patch > > > When NOT using 'sync' option, the NFS writes may issue the following warning: > org.apache.hadoop.hdfs.nfs.nfs3.OpenFileCtx: Got an overlapping write > (1248751616, 1249677312), nextOffset=1248752400. Silently drop it now > and the size of data copied via NFS will stay at 1248752400. > Found what happened is: > 1. The write requests from client are sent asynchronously. > 2. The NFS gateway has handler to handle the incoming requests by creating an > internal write request structuire and put it into cache; > 3. In parallel, a separate thread in NFS gateway takes requests out from the > cache and writes the data to HDFS. > The current offset is how much data has been written by the write thread in > 3. The detection of overlapping write request happens in 2, but it only > checks the write request against the curent offset, and trim the request if > necessary. Because the write requests are sent asynchronously, if two > requests are beyond the current offset, and they overlap, it's not detected > and both are put into the cache. This cause the symptom reported in this case > at step 3. -- This message was sent by Atlassian JIRA (v6.3.4#6332)