Return-Path: Delivered-To: apmail-lucene-hadoop-dev-archive@locus.apache.org Received: (qmail 70689 invoked from network); 21 Aug 2006 20:01:21 -0000 Received: from hermes.apache.org (HELO mail.apache.org) (209.237.227.199) by minotaur.apache.org with SMTP; 21 Aug 2006 20:01:21 -0000 Received: (qmail 97074 invoked by uid 500); 21 Aug 2006 20:01:21 -0000 Delivered-To: apmail-lucene-hadoop-dev-archive@lucene.apache.org Received: (qmail 96897 invoked by uid 500); 21 Aug 2006 20:01:21 -0000 Mailing-List: contact hadoop-dev-help@lucene.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: hadoop-dev@lucene.apache.org Delivered-To: mailing list hadoop-dev@lucene.apache.org Received: (qmail 96888 invoked by uid 99); 21 Aug 2006 20:01:21 -0000 Received: from asf.osuosl.org (HELO asf.osuosl.org) (140.211.166.49) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 21 Aug 2006 13:01:21 -0700 X-ASF-Spam-Status: No, hits=0.0 required=10.0 tests= X-Spam-Check-By: apache.org Received: from [209.237.227.198] (HELO brutus.apache.org) (209.237.227.198) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 21 Aug 2006 13:01:20 -0700 Received: from brutus (localhost [127.0.0.1]) by brutus.apache.org (Postfix) with ESMTP id A03487142F0 for ; Mon, 21 Aug 2006 19:58:16 +0000 (GMT) Message-ID: <30558623.1156190296653.JavaMail.jira@brutus> Date: Mon, 21 Aug 2006 12:58:16 -0700 (PDT) From: "Doug Cutting (JIRA)" To: hadoop-dev@lucene.apache.org Subject: [jira] Commented: (HADOOP-54) SequenceFile should compress blocks, not individual entries In-Reply-To: <442955632.1140640880483.JavaMail.jira@ajax.apache.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Virus-Checked: Checked by ClamAV on apache.org X-Spam-Rating: minotaur.apache.org 1.6.2 0/1000/N [ http://issues.apache.org/jira/browse/HADOOP-54?page=comments#action_12429515 ] Doug Cutting commented on HADOOP-54: ------------------------------------ Benchmarks should be run w/o the -check option and with the -fast option, no? > SequenceFile should compress blocks, not individual entries > ----------------------------------------------------------- > > Key: HADOOP-54 > URL: http://issues.apache.org/jira/browse/HADOOP-54 > Project: Hadoop > Issue Type: Improvement > Components: io > Affects Versions: 0.2.0 > Reporter: Doug Cutting > Assigned To: Arun C Murthy > Fix For: 0.6.0 > > Attachments: SequenceFile.20060821.patch, SequenceFile.20060821.perfomance.txt, SequenceFile.updated.final.patch, SequenceFiles.final.patch, SequenceFiles.patch, SequenceFilesII.patch, VIntCompressionResults.txt > > > SequenceFile will optionally compress individual values. But both compression and performance would be much better if sequences of keys and values are compressed together. Sync marks should only be placed between blocks. This will require some changes to MapFile too, so that all file positions stored there are the positions of blocks, not entries within blocks. Probably this can be accomplished by adding a getBlockStartPosition() method to SequenceFile.Writer. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira