Return-Path: Delivered-To: apmail-hadoop-mapreduce-user-archive@minotaur.apache.org Received: (qmail 79093 invoked from network); 9 Apr 2011 16:58:15 -0000 Received: from hermes.apache.org (HELO mail.apache.org) (140.211.11.3) by minotaur.apache.org with SMTP; 9 Apr 2011 16:58:15 -0000 Received: (qmail 76726 invoked by uid 500); 9 Apr 2011 16:58:14 -0000 Delivered-To: apmail-hadoop-mapreduce-user-archive@hadoop.apache.org Received: (qmail 76667 invoked by uid 500); 9 Apr 2011 16:58:14 -0000 Mailing-List: contact mapreduce-user-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: mapreduce-user@hadoop.apache.org Delivered-To: mailing list mapreduce-user@hadoop.apache.org Received: (qmail 76659 invoked by uid 99); 9 Apr 2011 16:58:14 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Sat, 09 Apr 2011 16:58:14 +0000 X-ASF-Spam-Status: No, hits=1.5 required=5.0 tests=FREEMAIL_ENVFROM_END_DIGIT,FREEMAIL_FROM,RCVD_IN_DNSWL_LOW,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (athena.apache.org: domain of psdc1978@gmail.com designates 209.85.212.48 as permitted sender) Received: from [209.85.212.48] (HELO mail-vw0-f48.google.com) (209.85.212.48) by apache.org (qpsmtpd/0.29) with ESMTP; Sat, 09 Apr 2011 16:58:08 +0000 Received: by vws7 with SMTP id 7so5226062vws.35 for ; Sat, 09 Apr 2011 09:57:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:date:message-id:subject:from:to :content-type; bh=4rxFVr6O4LIO5iCLcN2Eb672lJ6pGH/0/VSMcrY6ez0=; b=rNDJnpIiQzpx9HR+nKkD+wXAFWGpOpEUnVtNlVWgiDCDQz1wCn5ktXM9GQWKyYIQEL wiM3dIELT7GQJD+62T2+gDz34YxUjZhlLRIyHMmOQY69Dod+YxBCxbmE7GrBQHNGAe7o Tpr5F6OJNETy7+PFERyqsMHVj4mNFPnyQcqpE= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:date:message-id:subject:from:to:content-type; b=gxRQNANRsTSFdaNeO2K3kNnQMWsVfH80DlvdDhl501yMLd0RPJrmZ80B8ggq8rRxmE Q7iIpVtwCilBAgjFCdObA/VnLIzMtrSHNz+DJ9qEIC7BC4DOEmJ4aT5F+zfKLK2aQq7N Wth9+Ya4nBGPQFj4C+zyc9zVjVWxNBmskrKjM= MIME-Version: 1.0 Received: by 10.52.95.203 with SMTP id dm11mr90834vdb.213.1302368267445; Sat, 09 Apr 2011 09:57:47 -0700 (PDT) Received: by 10.52.158.229 with HTTP; Sat, 9 Apr 2011 09:57:47 -0700 (PDT) Date: Sat, 9 Apr 2011 17:57:47 +0100 Message-ID: Subject: Communication protocol between MR and HDFS From: Pedro Costa To: mapreduce-user Content-Type: text/plain; charset=ISO-8859-1 Hi, I was wondering what's the communication protocol between MapReduce and the HDFS. The MapReduce fetch and saves data blocks from HDFS by HTTP or by RPC? Thanks, -- PSC