Return-Path: Delivered-To: apmail-hadoop-hdfs-dev-archive@minotaur.apache.org Received: (qmail 81679 invoked from network); 11 Mar 2010 18:35:23 -0000 Received: from unknown (HELO mail.apache.org) (140.211.11.3) by 140.211.11.9 with SMTP; 11 Mar 2010 18:35:23 -0000 Received: (qmail 32764 invoked by uid 500); 11 Mar 2010 18:34:49 -0000 Delivered-To: apmail-hadoop-hdfs-dev-archive@hadoop.apache.org Received: (qmail 32707 invoked by uid 500); 11 Mar 2010 18:34:48 -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 32597 invoked by uid 99); 11 Mar 2010 18:34:48 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 11 Mar 2010 18:34:48 +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; Thu, 11 Mar 2010 18:34:47 +0000 Received: from brutus.apache.org (localhost [127.0.0.1]) by brutus.apache.org (Postfix) with ESMTP id 3DCDE234C4BF for ; Thu, 11 Mar 2010 18:34:27 +0000 (UTC) Message-ID: <594593939.208921268332467252.JavaMail.jira@brutus.apache.org> Date: Thu, 11 Mar 2010 18:34:27 +0000 (UTC) From: "dhruba borthakur (JIRA)" To: hdfs-dev@hadoop.apache.org Subject: [jira] Created: (HDFS-1034) Enhance datanode to read data and checksum file in parallel MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 Enhance datanode to read data and checksum file in parallel ----------------------------------------------------------- Key: HDFS-1034 URL: https://issues.apache.org/jira/browse/HDFS-1034 Project: Hadoop HDFS Issue Type: Improvement Reporter: dhruba borthakur Assignee: dhruba borthakur In the current HDFS implementation, a read of a block issued to the datanode results in a disk access to the checksum file followed by a disk access to the checksum file. It would be nice to be able to do these two IOs in parallel to reduce read latency. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.