From common-issues-return-10109-apmail-hadoop-common-issues-archive=hadoop.apache.org@hadoop.apache.org Tue Aug 10 17:04:40 2010 Return-Path: Delivered-To: apmail-hadoop-common-issues-archive@minotaur.apache.org Received: (qmail 76764 invoked from network); 10 Aug 2010 17:04:40 -0000 Received: from unknown (HELO mail.apache.org) (140.211.11.3) by 140.211.11.9 with SMTP; 10 Aug 2010 17:04:40 -0000 Received: (qmail 96007 invoked by uid 500); 10 Aug 2010 17:04:40 -0000 Delivered-To: apmail-hadoop-common-issues-archive@hadoop.apache.org Received: (qmail 95960 invoked by uid 500); 10 Aug 2010 17:04:39 -0000 Mailing-List: contact common-issues-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: common-issues@hadoop.apache.org Delivered-To: mailing list common-issues@hadoop.apache.org Received: (qmail 95952 invoked by uid 99); 10 Aug 2010 17:04:39 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 10 Aug 2010 17:04:39 +0000 X-ASF-Spam-Status: No, hits=-2000.0 required=10.0 tests=ALL_TRUSTED X-Spam-Check-By: apache.org Received: from [140.211.11.22] (HELO thor.apache.org) (140.211.11.22) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 10 Aug 2010 17:04:38 +0000 Received: from thor (localhost [127.0.0.1]) by thor.apache.org (8.13.8+Sun/8.13.8) with ESMTP id o7AH4ILB028330 for ; Tue, 10 Aug 2010 17:04:18 GMT Message-ID: <22529989.256841281459858384.JavaMail.jira@thor> Date: Tue, 10 Aug 2010 13:04:18 -0400 (EDT) From: "Hairong Kuang (JIRA)" To: common-issues@hadoop.apache.org Subject: [jira] Commented: (HADOOP-6889) Make RPC to have an option to timeout In-Reply-To: <30758566.75561280434516176.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/HADOOP-6889?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12896951#action_12896951 ] Hairong Kuang commented on HADOOP-6889: --------------------------------------- It looks that Java returns the same value for every call of System.indentifyHashcode(x) as long as int x remains the same. But I feel more comfortable using x as hashcode directly. Either ^ or + should be fine. But I think we should consistently use either ^ or +. > Make RPC to have an option to timeout > ------------------------------------- > > Key: HADOOP-6889 > URL: https://issues.apache.org/jira/browse/HADOOP-6889 > Project: Hadoop Common > Issue Type: New Feature > Components: ipc > Affects Versions: 0.22.0 > Reporter: Hairong Kuang > Assignee: Hairong Kuang > Fix For: 0.22.0, 0.20-append > > Attachments: ipcTimeout.patch, ipcTimeout1.patch, ipcTimeout2.patch > > > Currently Hadoop RPC does not timeout when the RPC server is alive. What it currently does is that a RPC client sends a ping to the server whenever a socket timeout happens. If the server is still alive, it continues to wait instead of throwing a SocketTimeoutException. This is to avoid a client to retry when a server is busy and thus making the server even busier. This works great if the RPC server is NameNode. > But Hadoop RPC is also used for some of client to DataNode communications, for example, for getting a replica's length. When a client comes across a problematic DataNode, it gets stuck and can not switch to a different DataNode. In this case, it would be better that the client receives a timeout exception. > I plan to add a new configuration ipc.client.max.pings that specifies the max number of pings that a client could try. If a response can not be received after the specified max number of pings, a SocketTimeoutException is thrown. If this configuration property is not set, a client maintains the current semantics, waiting forever. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.