From mapreduce-issues-return-85920-apmail-hadoop-mapreduce-issues-archive=hadoop.apache.org@hadoop.apache.org Thu Jul 7 13:21:12 2016 Return-Path: X-Original-To: apmail-hadoop-mapreduce-issues-archive@minotaur.apache.org Delivered-To: apmail-hadoop-mapreduce-issues-archive@minotaur.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id 0374410C01 for ; Thu, 7 Jul 2016 13:21:12 +0000 (UTC) Received: (qmail 7343 invoked by uid 500); 7 Jul 2016 13:21:11 -0000 Delivered-To: apmail-hadoop-mapreduce-issues-archive@hadoop.apache.org Received: (qmail 7278 invoked by uid 500); 7 Jul 2016 13:21:11 -0000 Mailing-List: contact mapreduce-issues-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Delivered-To: mailing list mapreduce-issues@hadoop.apache.org Received: (qmail 7244 invoked by uid 99); 7 Jul 2016 13:21:11 -0000 Received: from arcas.apache.org (HELO arcas) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 07 Jul 2016 13:21:11 +0000 Received: from arcas.apache.org (localhost [127.0.0.1]) by arcas (Postfix) with ESMTP id 216E42C02A7 for ; Thu, 7 Jul 2016 13:21:11 +0000 (UTC) Date: Thu, 7 Jul 2016 13:21:11 +0000 (UTC) From: "mingleizhang (JIRA)" To: mapreduce-issues@hadoop.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (MAPREDUCE-6729) Hitting performance and error when lots of files to write or read MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 [ https://issues.apache.org/jira/browse/MAPREDUCE-6729?page=3Dcom.atlas= sian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=3D= 15366080#comment-15366080 ]=20 mingleizhang commented on MAPREDUCE-6729: ----------------------------------------- Thanks Kai Zheng for review this code. > Hitting performance and error when lots of files to write or read > ----------------------------------------------------------------- > > Key: MAPREDUCE-6729 > URL: https://issues.apache.org/jira/browse/MAPREDUCE-6729 > Project: Hadoop Map/Reduce > Issue Type: Improvement > Components: benchmarks, performance, test > Reporter: mingleizhang > Assignee: mingleizhang > Priority: Minor > Labels: performance, test > Attachments: MR-6729.txt > > > When doing DFSIO test as a distributed i/o benchmark tool. Then especiall= y writes plenty of files to disk or read from, both can cause performance i= ssue and imprecise value in a way. The question is that existing practices = needs to delete files when before running a job and that will cause extra t= ime consumption and furthermore cause performance issue, statistical time e= rror and imprecise throughput while the files are lots of. So we need to re= place or improve this hack to prevent this from happening in the future. > {code} > public static void testWrite() throws Exception { > FileSystem fs =3D cluster.getFileSystem(); > long tStart =3D System.currentTimeMillis(); > bench.writeTest(fs); // this line of code will cause extra time consu= mption because of fs.delete(*,*) by the writeTest method > long execTime =3D System.currentTimeMillis() - tStart; > bench.analyzeResult(fs, TestType.TEST_TYPE_WRITE, execTime); > } > private void writeTest(FileSystem fs) throws IOException { > Path writeDir =3D getWriteDir(config); > fs.delete(getDataDir(config), true); > fs.delete(writeDir, true); =20 > runIOTest(WriteMapper.class, writeDir); > } > {code}=E3=80=80 > [https://github.com/apache/hadoop/blob/trunk/hadoop-mapreduce-project/had= oop-mapreduce-client/hadoop-mapreduce-client-jobclient/src/test/java/org/ap= ache/hadoop/fs/TestDFSIO.java] -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: mapreduce-issues-unsubscribe@hadoop.apache.org For additional commands, e-mail: mapreduce-issues-help@hadoop.apache.org