Return-Path: Delivered-To: apmail-hadoop-hdfs-dev-archive@minotaur.apache.org Received: (qmail 99831 invoked from network); 9 Nov 2009 19:40:04 -0000 Received: from hermes.apache.org (HELO mail.apache.org) (140.211.11.3) by minotaur.apache.org with SMTP; 9 Nov 2009 19:40:04 -0000 Received: (qmail 74766 invoked by uid 500); 9 Nov 2009 19:40:04 -0000 Delivered-To: apmail-hadoop-hdfs-dev-archive@hadoop.apache.org Received: (qmail 74699 invoked by uid 500); 9 Nov 2009 19:40:04 -0000 Mailing-List: contact hdfs-dev-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: hdfs-dev@hadoop.apache.org Delivered-To: mailing list hdfs-dev@hadoop.apache.org Received: (qmail 74689 invoked by uid 99); 9 Nov 2009 19:40:04 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 09 Nov 2009 19:40:04 +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; Mon, 09 Nov 2009 19:39:53 +0000 Received: from brutus (localhost [127.0.0.1]) by brutus.apache.org (Postfix) with ESMTP id 75E1C234C046 for ; Mon, 9 Nov 2009 11:39:32 -0800 (PST) Message-ID: <1528274060.1257795572468.JavaMail.jira@brutus> Date: Mon, 9 Nov 2009 19:39:32 +0000 (UTC) From: "dhruba borthakur (JIRA)" To: hdfs-dev@hadoop.apache.org Subject: [jira] Resolved: (HDFS-503) Implement erasure coding as a layer on HDFS In-Reply-To: <1790768686.1248420974999.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 resolved HDFS-503. ----------------------------------- Resolution: Fixed I will fix the unit-test failure via HDFS-757. The unit tests failed when Maven integration code was checked into HDFS. > 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 > Components: contrib/raid > Reporter: dhruba borthakur > Assignee: dhruba borthakur > Fix For: 0.22.0 > > Attachments: raid1.txt, raid2.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.