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Yi Liu commented on YARN-2996: ------------------------------ Thanks [~zjshen] for review and commit. > Refine fs operations in FileSystemRMStateStore and few fixes > ------------------------------------------------------------ > > Key: YARN-2996 > URL: https://issues.apache.org/jira/browse/YARN-2996 > Project: Hadoop YARN > Issue Type: Improvement > Components: resourcemanager > Reporter: Yi Liu > Assignee: Yi Liu > Fix For: 2.7.0 > > Attachments: YARN-2996.001.patch, YARN-2996.002.patch, > YARN-2996.003.patch, YARN-2996.004.patch > > > In {{FileSystemRMStateStore}}, we can refine some fs operations to improve > performance: > *1.* There are several places invoke {{fs.exists}}, then > {{fs.getFileStatus}}, we can merge them to save one RPC call > {code} > if (fs.exists(versionNodePath)) { > FileStatus status = fs.getFileStatus(versionNodePath); > {code} > *2.* > {code} > protected void updateFile(Path outputPath, byte[] data) throws Exception { > Path newPath = new Path(outputPath.getParent(), outputPath.getName() + > ".new"); > // use writeFile to make sure .new file is created atomically > writeFile(newPath, data); > replaceFile(newPath, outputPath); > } > {code} > The {{updateFile}} is not good too, it write file to _output\_file_.tmp, then > rename to _output\_file_.new, then rename it to _output\_file_, we can reduce > one rename operation. > Also there is one unnecessary import, we can remove it. -- This message was sent by Atlassian JIRA (v6.3.4#6332)