Return-Path: X-Original-To: apmail-hadoop-user-archive@minotaur.apache.org Delivered-To: apmail-hadoop-user-archive@minotaur.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id D2498D582 for ; Sun, 7 Oct 2012 14:45:51 +0000 (UTC) Received: (qmail 13923 invoked by uid 500); 7 Oct 2012 14:45:46 -0000 Delivered-To: apmail-hadoop-user-archive@hadoop.apache.org Received: (qmail 13819 invoked by uid 500); 7 Oct 2012 14:45:46 -0000 Mailing-List: contact user-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@hadoop.apache.org Delivered-To: mailing list user@hadoop.apache.org Received: (qmail 13812 invoked by uid 99); 7 Oct 2012 14:45:46 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Sun, 07 Oct 2012 14:45:46 +0000 X-ASF-Spam-Status: No, hits=3.2 required=5.0 tests=FREEMAIL_REPLY,HTML_MESSAGE,RCVD_IN_DNSWL_NONE,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (nike.apache.org: domain of michael_segel@hotmail.com designates 65.55.111.93 as permitted sender) Received: from [65.55.111.93] (HELO blu0-omc2-s18.blu0.hotmail.com) (65.55.111.93) by apache.org (qpsmtpd/0.29) with ESMTP; Sun, 07 Oct 2012 14:45:36 +0000 Received: from BLU0-SMTP291 ([65.55.111.71]) by blu0-omc2-s18.blu0.hotmail.com with Microsoft SMTPSVC(6.0.3790.4675); Sun, 7 Oct 2012 07:45:15 -0700 X-Originating-IP: [173.15.87.37] X-EIP: [80mR165hcVAu2PWuPueoxKtF1F59eVTs] X-Originating-Email: [michael_segel@hotmail.com] Message-ID: Received: from [192.168.0.104] ([173.15.87.37]) by BLU0-SMTP291.blu0.hotmail.com over TLS secured channel with Microsoft SMTPSVC(6.0.3790.4675); Sun, 7 Oct 2012 07:45:13 -0700 From: Michael Segel Content-Type: multipart/alternative; boundary="Apple-Mail=_5FFBD876-C8C0-4CFF-A874-4761C52DF435" MIME-Version: 1.0 (Mac OS X Mail 6.1 \(1498\)) Subject: Re: What is the difference between Rack-local map tasks and Data-local map tasks? Date: Sun, 7 Oct 2012 09:45:12 -0500 References: To: user@hadoop.apache.org In-Reply-To: X-Mailer: Apple Mail (2.1498) X-OriginalArrivalTime: 07 Oct 2012 14:45:13.0839 (UTC) FILETIME=[5BF627F0:01CDA49A] --Apple-Mail=_5FFBD876-C8C0-4CFF-A874-4761C52DF435 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="iso-8859-1" Rack local means that while the data isn't local to the node running the = task, it is still on the same rack.=20 (Its meaningless unless you've set up rack awareness because all of the = machines are on the default rack. ) Data local means that the task is running local to the machine that = contains the actual data.=20 HTH -Mike On Oct 7, 2012, at 8:56 AM, centerqi hu wrote: >=20 > hi all > When I run "hadoop job -status xxx",Output the following some list. >=20 > Rack-local map tasks=3D124 > Data-local map tasks=3D6 > What is the difference between Rack-local map tasks and Data-local map = tasks? >=20 > --=20 > centerqi@gmail.com|Sam --Apple-Mail=_5FFBD876-C8C0-4CFF-A874-4761C52DF435 Content-Transfer-Encoding: 7bit Content-Type: text/html; charset="iso-8859-1" Rack local means that while the data isn't local to the node running the task, it is still on the same rack. 
(Its meaningless unless you've set up rack awareness because all of the machines are on the default rack. )

Data local means that the task is running local to the machine that contains the actual data. 

HTH

-Mike

On Oct 7, 2012, at 8:56 AM, centerqi hu <centerqi@gmail.com> wrote:


hi all

When I run "hadoop job -status xxx",Output the following some list.

Rack-local map tasks=124
Data-local map tasks=6

What is the difference between Rack-local map tasks and Data-local map tasks?

--
centerqi@gmail.com|Sam

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