Return-Path: Delivered-To: apmail-hadoop-core-dev-archive@www.apache.org Received: (qmail 73734 invoked from network); 22 Jan 2008 19:12:01 -0000 Received: from hermes.apache.org (HELO mail.apache.org) (140.211.11.2) by minotaur.apache.org with SMTP; 22 Jan 2008 19:12:01 -0000 Received: (qmail 61877 invoked by uid 500); 22 Jan 2008 19:11:50 -0000 Delivered-To: apmail-hadoop-core-dev-archive@hadoop.apache.org Received: (qmail 61653 invoked by uid 500); 22 Jan 2008 19:11:49 -0000 Mailing-List: contact core-dev-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: core-dev@hadoop.apache.org Delivered-To: mailing list core-dev@hadoop.apache.org Received: (qmail 61644 invoked by uid 500); 22 Jan 2008 19:11:49 -0000 Delivered-To: apmail-lucene-hadoop-dev@lucene.apache.org Received: (qmail 61641 invoked by uid 99); 22 Jan 2008 19:11:49 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 22 Jan 2008 11:11:49 -0800 X-ASF-Spam-Status: No, hits=-98.0 required=10.0 tests=ALL_TRUSTED,URIBL_BLACK X-Spam-Check-By: apache.org Received: from [140.211.11.4] (HELO brutus.apache.org) (140.211.11.4) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 22 Jan 2008 19:11:43 +0000 Received: from brutus (localhost [127.0.0.1]) by brutus.apache.org (Postfix) with ESMTP id CAAAF714274 for ; Tue, 22 Jan 2008 11:11:35 -0800 (PST) Message-ID: <17396942.1201029095827.JavaMail.jira@brutus> Date: Tue, 22 Jan 2008 11:11:35 -0800 (PST) From: "Joydeep Sen Sarma (JIRA)" To: hadoop-dev@lucene.apache.org Subject: [jira] Commented: (HADOOP-2393) healthy tasks dying because unable to ping tasktracker In-Reply-To: <25468949.1197309523496.JavaMail.jira@brutus> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Virus-Checked: Checked by ClamAV on apache.org [ https://issues.apache.org/jira/browse/HADOOP-2393?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12561423#action_12561423 ] Joydeep Sen Sarma commented on HADOOP-2393: ------------------------------------------- that would seem acceptable. on similar lines - the start-stop scripts look at the pids file to detect if the tasktracker is running. we could use the same logic (signal the tasktracker pid to see if it's alive). dunno if this is easily doable in java. > healthy tasks dying because unable to ping tasktracker > ------------------------------------------------------ > > Key: HADOOP-2393 > URL: https://issues.apache.org/jira/browse/HADOOP-2393 > Project: Hadoop > Issue Type: Bug > Components: mapred > Affects Versions: 0.14.4 > Environment: 0.13.1, quad-code x86-64, FC-linux. -xmx2048 > ipc.client.timeout = 10000 > Reporter: Joydeep Sen Sarma > Priority: Critical > > we have some bad jobs where the reduces are getting stalled (for unknown reason). The task tracker kills these processes from time to time. > Everytime one of these events happens - other (healthy) map tasks in the same node are also killed. Looking at the logs and code up to 0.14.3 - it seems like the child tasks pings to the task tracker are timed out and the child task self-terminates. > tasktracker log: > // notice the good 10+ second gap in logs on otherwise busy node: > 2007-12-10 09:26:53,047 INFO org.apache.hadoop.mapred.TaskRunner: task_0120_r_000001_47 done; removing files. > 2007-12-10 09:27:26,878 INFO org.apache.hadoop.mapred.TaskRunner: task_0120_m_000618_0 done; removing files. > 2007-12-10 09:27:26,883 INFO org.apache.hadoop.ipc.Server: Process Thread Dump: Discarding call ping(task_0149_m_000007_0) from 10.16.158.113:43941 > 24 active threads > ... huge stack trace dump in logfile ... > something was going on at this time which caused to the tasktracker to essentially stall. all the pings are discarded. after stack trace dump: > 2007-12-10 09:27:26,883 WARN org.apache.hadoop.ipc.Server: IPC Server handler 0 on 50050, call ping(task_0149_m_000007_0) from 10.16.158.113:43941:\ > discarded for being too old (21380) > 2007-12-10 09:27:26,883 WARN org.apache.hadoop.ipc.Server: IPC Server handler 1 on 50050, call ping(task_0149_m_000002_1) from 10.16.158.113:44183:\ > discarded for being too old (21380) > 2007-12-10 09:27:26,883 WARN org.apache.hadoop.ipc.Server: IPC Server handler 0 on 50050, call ping(task_0149_m_000007_0) from 10.16.158.113:43941:\ > discarded for being too old (10367) > 2007-12-10 09:27:26,883 WARN org.apache.hadoop.ipc.Server: IPC Server handler 1 on 50050, call ping(task_0149_m_000002_1) from 10.16.158.113:44183:\ > discarded for being too old (10360) > 2007-12-10 09:27:26,982 WARN org.apache.hadoop.mapred.TaskRunner: task_0149_m_000002_1 Child Error > looking at code, failure of client to ping causes termination: > else { > // send ping > taskFound = umbilical.ping(taskId); > } > ... > catch (Throwable t) { > LOG.info("Communication exception: " + StringUtils.stringifyException(t)); > remainingRetries -=1; > if (remainingRetries == 0) { > ReflectionUtils.logThreadInfo(LOG, "Communication exception", 0); > LOG.warn("Last retry, killing "+taskId); > System.exit(65); > exit code is 65 as reported by task tracker. > i don't see an option to turn off stack trace dump (which could be a likely cause) - and i would hate to bump up timeout because of this. Crap. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.