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Hadoop QA commented on HADOOP-12079: ------------------------------------ \\ \\ | (x) *{color:red}-1 overall{color}* | \\ \\ || Vote || Subsystem || Runtime || Comment || | {color:blue}0{color} | pre-patch | 15m 13s | 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 30s | There were no new javac warning messages. | | {color:green}+1{color} | javadoc | 9m 36s | There were no new javadoc warning messages. | | {color:green}+1{color} | release audit | 0m 22s | The applied patch does not increase the total number of release audit warnings. | | {color:red}-1{color} | checkstyle | 0m 19s | The applied patch generated 1 new checkstyle issues (total was 294, now 295). | | {color:green}+1{color} | whitespace | 0m 0s | The patch has no lines that end in whitespace. | | {color:green}+1{color} | install | 1m 35s | mvn install still works. | | {color:green}+1{color} | eclipse:eclipse | 0m 34s | The patch built with eclipse:eclipse. | | {color:green}+1{color} | findbugs | 0m 45s | The patch does not introduce any new Findbugs (version 3.0.0) warnings. | | {color:green}+1{color} | tools/hadoop tests | 0m 14s | Tests passed in hadoop-openstack. | | | | 36m 18s | | \\ \\ || Subsystem || Report/Notes || | Patch URL | http://issues.apache.org/jira/secure/attachment/12738852/x-newest-optional0002.patch | | Optional Tests | javadoc javac unit findbugs checkstyle | | git revision | trunk / c7729ef | | checkstyle | https://builds.apache.org/job/PreCommit-HADOOP-Build/6950/artifact/patchprocess/diffcheckstylehadoop-openstack.txt | | hadoop-openstack test log | https://builds.apache.org/job/PreCommit-HADOOP-Build/6950/artifact/patchprocess/testrun_hadoop-openstack.txt | | Test Results | https://builds.apache.org/job/PreCommit-HADOOP-Build/6950/testReport/ | | Java | 1.7.0_55 | | uname | Linux asf906.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-HADOOP-Build/6950/console | This message was automatically generated. > Make 'X-Newest' header a configurable > ------------------------------------- > > Key: HADOOP-12079 > URL: https://issues.apache.org/jira/browse/HADOOP-12079 > Project: Hadoop Common > Issue Type: Improvement > Components: fs/swift > Affects Versions: 3.0.0, 2.6.0 > Reporter: Gil Vernik > Assignee: Gil Vernik > Fix For: 3.0.0, 2.6.1 > > Attachments: x-newest-optional0001.patch, x-newest-optional0002.patch > > > Current code always sends X-Newest header to Swift. While it's true that > Swift is eventual consistent and X-Newest will always get the newest version > from Swift, in practice this header will make Swift response very slow. > This header should be configured as an optional, so that it will be possible > to access Swift without this header and get much better performance. > This patch doesn't modify current behavior. All is working as is, but there > is an option to provide fs.swift.service.useXNewest = false. > Some background on Swift and X-Newest: > When a GET or HEAD request is made to an object, the default behavior is to > get the data from one of the replicas (could be any of them). The downside to > this is that if there are older versions of the object (due to eventual > consistency) it is possible to get an older version of the object. The upside > is that the for the majority of use cases, this isn't an issue. For the small > subset of use cases that need to make sure that they get the latest version > of the object, they can set the "X-Newest" header to "True". If this is set, > the proxy server will check all replicas of the object and only return the > newest object. The downside to this is that the request can take longer, > since it has to contact all the replicas. It is also more expensive for the > backend, so only recommended when it is absolutely needed. -- This message was sent by Atlassian JIRA (v6.3.4#6332)