Return-Path: Delivered-To: apmail-hadoop-mapreduce-dev-archive@minotaur.apache.org Received: (qmail 56063 invoked from network); 25 Apr 2010 02:01:46 -0000 Received: from unknown (HELO mail.apache.org) (140.211.11.3) by 140.211.11.9 with SMTP; 25 Apr 2010 02:01:46 -0000 Received: (qmail 5704 invoked by uid 500); 25 Apr 2010 02:01:46 -0000 Delivered-To: apmail-hadoop-mapreduce-dev-archive@hadoop.apache.org Received: (qmail 5655 invoked by uid 500); 25 Apr 2010 02:01:45 -0000 Mailing-List: contact mapreduce-dev-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: mapreduce-dev@hadoop.apache.org Delivered-To: mailing list mapreduce-dev@hadoop.apache.org Received: (qmail 5647 invoked by uid 99); 25 Apr 2010 02:01:45 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Sun, 25 Apr 2010 02:01:45 +0000 X-ASF-Spam-Status: No, hits=4.4 required=10.0 tests=AWL,FREEMAIL_ENVFROM_END_DIGIT,FREEMAIL_FROM,HTML_MESSAGE,SPF_PASS,T_TO_NO_BRKTS_FREEMAIL X-Spam-Check-By: apache.org Received-SPF: pass (athena.apache.org: domain of ashahzad4@gmail.com designates 74.125.82.48 as permitted sender) Received: from [74.125.82.48] (HELO mail-ww0-f48.google.com) (74.125.82.48) by apache.org (qpsmtpd/0.29) with ESMTP; Sun, 25 Apr 2010 02:01:39 +0000 Received: by wwi14 with SMTP id 14so536288wwi.35 for ; Sat, 24 Apr 2010 19:01:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:received:date:message-id :subject:from:to:content-type; bh=A2FU/RB4wp1g4UNI2MjLAHutq+3uaq3m6uSpfHdeOgg=; b=GFqP+GZNUqa+idhgw9ujAYu90JEXxP7gAmVCRNKhDELyCAvGE3cF/bshiJ5rbVtk0S eQaSDE0OBSE3FA0ak3j4ocPcQGgoijDGwcT3ifh8wLDCH5q7mXUO1D+AffJfIH/UY0d+ S7+savUEGLMhC+wnQJKYVxZAxEDNTxn9MYghY= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:date:message-id:subject:from:to:content-type; b=wygiYY4FnIwQNzLhL+4DMEDkwRfz1SkVpkyk7ge95ArZ7ZPZTt9aMknnxCXLcmRWFp XrZFCglj70mSht2iOj0v5PdO57dO1BEMnxSy2aj1T8MGabXpBtwUwpPkLR2K0hMqMNwq aRFE/CpWVZs+i2xJJdKgjiRsck3VWSCRKGbf8= MIME-Version: 1.0 Received: by 10.216.90.206 with SMTP id e56mr2619754wef.167.1272160878209; Sat, 24 Apr 2010 19:01:18 -0700 (PDT) Received: by 10.216.156.83 with HTTP; Sat, 24 Apr 2010 19:01:18 -0700 (PDT) Date: Sun, 25 Apr 2010 04:01:18 +0200 Message-ID: Subject: issue regarding shuffle process in hadoop mapreduce From: Ahmad Shahzad To: mapreduce-dev@hadoop.apache.org Content-Type: multipart/alternative; boundary=001636e1ee403e2aee04850609ca --001636e1ee403e2aee04850609ca Content-Type: text/plain; charset=ISO-8859-1 Hey All, Can anyone tell me that how does the shuffle process that happens after the mapping task takes place. Is it the responsibility of mappers to push data to the reducers or is it the responsibility of task trackers to shuffle the data to the reducers. And which communication protocol does shuffle process use to shuffle. Regards, Ahmad Shahzad --001636e1ee403e2aee04850609ca--