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Hadoop QA commented on HDFS-4960: --------------------------------- {color:red}-1 overall{color}. Here are the results of testing the latest attachment http://issues.apache.org/jira/secure/attachment/12591131/4960-trunk.patch against trunk revision . {color:green}+1 @author{color}. The patch does not contain any @author tags. {color:red}-1 tests included{color}. The patch doesn't appear to include any new or modified tests. Please justify why no new tests are needed for this patch. Also please list what manual steps were performed to verify this patch. {color:green}+1 javac{color}. The applied patch does not increase the total number of javac compiler warnings. {color:green}+1 javadoc{color}. The javadoc tool did not generate any warning messages. {color:green}+1 eclipse:eclipse{color}. The patch built with eclipse:eclipse. {color:green}+1 findbugs{color}. The patch does not introduce any new Findbugs (version 1.3.9) warnings. {color:green}+1 release audit{color}. The applied patch does not increase the total number of release audit warnings. {color:green}+1 core tests{color}. The patch passed unit tests in hadoop-hdfs-project/hadoop-hdfs. {color:green}+1 contrib tests{color}. The patch passed contrib unit tests. Test results: https://builds.apache.org/job/PreCommit-HDFS-Build/4600//testReport/ Console output: https://builds.apache.org/job/PreCommit-HDFS-Build/4600//console This message is automatically generated. > Unnecessary .meta seeks even when skip checksum is true > ------------------------------------------------------- > > Key: HDFS-4960 > URL: https://issues.apache.org/jira/browse/HDFS-4960 > Project: Hadoop HDFS > Issue Type: Bug > Affects Versions: 3.0.0, 2.1.0-beta > Reporter: Varun Sharma > Assignee: Varun Sharma > Attachments: 4960-branch2.patch, 4960-trunk.patch > > > While attempting to benchmark an HBase + Hadoop 2.0 setup on SSDs, we found > unnecessary seeks into .meta files, each seek was a 7 byte read at the head > of the file - this attempts to validate the version #. Since the client is > requesting no-checksum, we should not be needing to touch the .meta file at > all. > Since the purpose of skip checksum is to also avoid the performance penalty > of the extra seek, we should not be seeking into .meta if skip checksum is > true -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira