Return-Path: Delivered-To: apmail-hadoop-hdfs-issues-archive@minotaur.apache.org Received: (qmail 5038 invoked from network); 3 Jun 2010 20:32:20 -0000 Received: from unknown (HELO mail.apache.org) (140.211.11.3) by 140.211.11.9 with SMTP; 3 Jun 2010 20:32:20 -0000 Received: (qmail 9654 invoked by uid 500); 3 Jun 2010 20:32:20 -0000 Delivered-To: apmail-hadoop-hdfs-issues-archive@hadoop.apache.org Received: (qmail 9616 invoked by uid 500); 3 Jun 2010 20:32:20 -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 9608 invoked by uid 99); 3 Jun 2010 20:32:20 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 03 Jun 2010 20:32:20 +0000 X-ASF-Spam-Status: No, hits=-1495.3 required=10.0 tests=ALL_TRUSTED,AWL X-Spam-Check-By: apache.org Received: from [140.211.11.22] (HELO thor.apache.org) (140.211.11.22) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 03 Jun 2010 20:32:19 +0000 Received: from thor (localhost [127.0.0.1]) by thor.apache.org (8.13.8+Sun/8.13.8) with ESMTP id o53KVxDL004152 for ; Thu, 3 Jun 2010 20:31:59 GMT Message-ID: <18578194.167331275597119598.JavaMail.jira@thor> Date: Thu, 3 Jun 2010 16:31:59 -0400 (EDT) From: "Suresh Srinivas (JIRA)" To: hdfs-issues@hadoop.apache.org Subject: [jira] Commented: (HDFS-1110) Namenode heap optimization - reuse objects for commonly used file names In-Reply-To: <26851282.14551272307412975.JavaMail.jira@thor> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 [ https://issues.apache.org/jira/browse/HDFS-1110?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12875285#action_12875285 ] Suresh Srinivas commented on HDFS-1110: --------------------------------------- Alternatively we can follow the convention in java.util.Dictionary: # Change the method name from lookup to put # Add methods get and remove for completeness > Namenode heap optimization - reuse objects for commonly used file names > ----------------------------------------------------------------------- > > Key: HDFS-1110 > URL: https://issues.apache.org/jira/browse/HDFS-1110 > Project: Hadoop HDFS > Issue Type: Improvement > Reporter: Suresh Srinivas > Assignee: Suresh Srinivas > Fix For: 0.22.0 > > Attachments: hdfs-1110.2.patch, hdfs-1110.3.patch, hdfs-1110.patch > > > There are a lot of common file names used in HDFS, mainly created by mapreduce, such as file names starting with "part". Reusing byte[] corresponding to these recurring file names will save significant heap space used for storing the file names in millions of INodeFile objects. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.