Return-Path: Delivered-To: apmail-hadoop-hdfs-issues-archive@minotaur.apache.org Received: (qmail 17488 invoked from network); 29 Aug 2009 00:19:04 -0000 Received: from hermes.apache.org (HELO mail.apache.org) (140.211.11.3) by minotaur.apache.org with SMTP; 29 Aug 2009 00:19:04 -0000 Received: (qmail 61949 invoked by uid 500); 29 Aug 2009 00:19:04 -0000 Delivered-To: apmail-hadoop-hdfs-issues-archive@hadoop.apache.org Received: (qmail 61893 invoked by uid 500); 29 Aug 2009 00:19:04 -0000 Mailing-List: contact hdfs-issues-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: hdfs-issues@hadoop.apache.org Delivered-To: mailing list hdfs-issues@hadoop.apache.org Received: (qmail 61880 invoked by uid 99); 29 Aug 2009 00:19:04 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Sat, 29 Aug 2009 00:19:04 +0000 X-ASF-Spam-Status: No, hits=-2000.0 required=10.0 tests=ALL_TRUSTED X-Spam-Check-By: apache.org Received: from [140.211.11.140] (HELO brutus.apache.org) (140.211.11.140) by apache.org (qpsmtpd/0.29) with ESMTP; Sat, 29 Aug 2009 00:18:53 +0000 Received: from brutus (localhost [127.0.0.1]) by brutus.apache.org (Postfix) with ESMTP id BC829234C044 for ; Fri, 28 Aug 2009 17:18:32 -0700 (PDT) Message-ID: <1722724425.1251505112770.JavaMail.jira@brutus> Date: Fri, 28 Aug 2009 17:18:32 -0700 (PDT) From: "dhruba borthakur (JIRA)" To: hdfs-issues@hadoop.apache.org Subject: [jira] Updated: (HDFS-503) Implement erasure coding as a layer on HDFS In-Reply-To: <242063006.1248420974911.JavaMail.jira@brutus> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 X-Virus-Checked: Checked by ClamAV on apache.org [ https://issues.apache.org/jira/browse/HDFS-503?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] dhruba borthakur updated HDFS-503: ---------------------------------- Tags: fb > Implement erasure coding as a layer on HDFS > ------------------------------------------- > > Key: HDFS-503 > URL: https://issues.apache.org/jira/browse/HDFS-503 > Project: Hadoop HDFS > Issue Type: New Feature > Reporter: dhruba borthakur > Assignee: dhruba borthakur > Attachments: raid1.txt > > > The goal of this JIRA is to discuss how the cost of raw storage for a HDFS file system can be reduced. Keeping three copies of the same data is very costly, especially when the size of storage is huge. One idea is to reduce the replication factor and do erasure coding of a set of blocks so that the over probability of failure of a block remains the same as before. > Many forms of error-correcting codes are available, see http://en.wikipedia.org/wiki/Erasure_code. Also, recent research from CMU has described DiskReduce https://opencirrus.org/system/files/Gibson-OpenCirrus-June9-09.ppt. > My opinion is to discuss implementation strategies that are not part of base HDFS, but is a layer on top of HDFS. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.