Return-Path: X-Original-To: apmail-hadoop-yarn-issues-archive@minotaur.apache.org Delivered-To: apmail-hadoop-yarn-issues-archive@minotaur.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id 39E5618FC1 for ; Tue, 30 Jun 2015 17:58:06 +0000 (UTC) Received: (qmail 52018 invoked by uid 500); 30 Jun 2015 17:58:06 -0000 Delivered-To: apmail-hadoop-yarn-issues-archive@hadoop.apache.org Received: (qmail 51979 invoked by uid 500); 30 Jun 2015 17:58:06 -0000 Mailing-List: contact yarn-issues-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: yarn-issues@hadoop.apache.org Delivered-To: mailing list yarn-issues@hadoop.apache.org Received: (qmail 51966 invoked by uid 99); 30 Jun 2015 17:58:05 -0000 Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 30 Jun 2015 17:58:05 +0000 Date: Tue, 30 Jun 2015 17:58:05 +0000 (UTC) From: "Varun Saxena (JIRA)" To: yarn-issues@hadoop.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (YARN-3508) Preemption processing occuring on the main RM dispatcher 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/YARN-3508?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14608746#comment-14608746 ] Varun Saxena commented on YARN-3508: ------------------------------------ [~leftnoteasy], yes this is what the patch does and addresses the issue in hand. I thought you want me to put events directly to Scheduler Event Queue and hence bypass Central RM Dispatcher Queue. Anyways just to explain, below is what I have done. I have removed {{ContainerPreemptEventType}} and moved all these events to {{SchedulerEventType}}. I have also removed {{RMContainerPreemptEventDispatcher}} because that processes the events synchronously as part of RMDispatcher Event Thread. As per patch the events from {{ProportionalCapacityPreemptionPolicy}} are sent to central RM Dispatcher and as the event type is {{SchedulerEventType}}, the preemption events are sent to scheduler event queue. Then the Scheduler Dispatcher picks up these events from scheduler event queue and call {{CapacityScheduler#handle}} which then calls the relevant method to handle different preemption events. I added a test case too for this behavior by adding a new test class {{TestRMDispatcher}}. > Preemption processing occuring on the main RM dispatcher > -------------------------------------------------------- > > Key: YARN-3508 > URL: https://issues.apache.org/jira/browse/YARN-3508 > Project: Hadoop YARN > Issue Type: Bug > Components: resourcemanager, scheduler > Affects Versions: 2.6.0 > Reporter: Jason Lowe > Assignee: Varun Saxena > Attachments: YARN-3508.002.patch, YARN-3508.01.patch, YARN-3508.03.patch, YARN-3508.04.patch > > > We recently saw the RM for a large cluster lag far behind on the AsyncDispacher event queue. The AsyncDispatcher thread was consistently blocked on the highly-contended CapacityScheduler lock trying to dispatch preemption-related events for RMContainerPreemptEventDispatcher. Preemption processing should occur on the scheduler event dispatcher thread or a separate thread to avoid delaying the processing of other events in the primary dispatcher queue. -- This message was sent by Atlassian JIRA (v6.3.4#6332)