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 58707D218 for ; Mon, 6 Aug 2012 20:49:05 +0000 (UTC) Received: (qmail 50544 invoked by uid 500); 6 Aug 2012 20:49:05 -0000 Delivered-To: apmail-hadoop-mapreduce-issues-archive@hadoop.apache.org Received: (qmail 50492 invoked by uid 500); 6 Aug 2012 20:49:05 -0000 Mailing-List: contact mapreduce-issues-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: mapreduce-issues@hadoop.apache.org Delivered-To: mailing list mapreduce-issues@hadoop.apache.org Received: (qmail 50480 invoked by uid 99); 6 Aug 2012 20:49:05 -0000 Received: from issues-vm.apache.org (HELO issues-vm) (140.211.11.160) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 06 Aug 2012 20:49:05 +0000 Received: from isssues-vm.apache.org (localhost [127.0.0.1]) by issues-vm (Postfix) with ESMTP id 0815D14284D for ; Mon, 6 Aug 2012 20:49:05 +0000 (UTC) Date: Mon, 6 Aug 2012 20:49:05 +0000 (UTC) From: "Ahmed Radwan (JIRA)" To: mapreduce-issues@hadoop.apache.org Message-ID: <313807565.18260.1344286145034.JavaMail.jiratomcat@issues-vm> In-Reply-To: <784234789.92822.1343076214657.JavaMail.jiratomcat@issues-vm> Subject: [jira] [Updated] (MAPREDUCE-4469) Resource calculation in child tasks is CPU-heavy MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 [ https://issues.apache.org/jira/browse/MAPREDUCE-4469?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Ahmed Radwan updated MAPREDUCE-4469: ------------------------------------ Assignee: Ahmed Radwan > Resource calculation in child tasks is CPU-heavy > ------------------------------------------------ > > Key: MAPREDUCE-4469 > URL: https://issues.apache.org/jira/browse/MAPREDUCE-4469 > Project: Hadoop Map/Reduce > Issue Type: Bug > Components: performance, task > Affects Versions: 1.0.3 > Reporter: Todd Lipcon > Assignee: Ahmed Radwan > Attachments: MAPREDUCE-4469.patch > > > In doing some benchmarking on a hadoop-1 derived codebase, I noticed that each of the child tasks was doing a ton of syscalls. Upon stracing, I noticed that it's spending a lot of time looping through all the files in /proc to calculate resource usage. > As a test, I added a flag to disable use of the ResourceCalculatorPlugin within the tasks. On a CPU-bound 500G-sort workload, this improved total job runtime by about 10% (map slot-seconds by 14%, reduce slot seconds by 8%) -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira