Return-Path: X-Original-To: archive-asf-public-internal@cust-asf2.ponee.io Delivered-To: archive-asf-public-internal@cust-asf2.ponee.io Received: from cust-asf.ponee.io (cust-asf.ponee.io [163.172.22.183]) by cust-asf2.ponee.io (Postfix) with ESMTP id 13C48200BAE for ; Fri, 28 Oct 2016 23:37:00 +0200 (CEST) Received: by cust-asf.ponee.io (Postfix) id 12893160AE4; Fri, 28 Oct 2016 21:37:00 +0000 (UTC) Delivered-To: archive-asf-public@cust-asf.ponee.io Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by cust-asf.ponee.io (Postfix) with SMTP id 5AC0F160ACA for ; Fri, 28 Oct 2016 23:36:59 +0200 (CEST) Received: (qmail 86088 invoked by uid 500); 28 Oct 2016 21:36:58 -0000 Mailing-List: contact issues-help@ambari.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@ambari.apache.org Delivered-To: mailing list issues@ambari.apache.org Received: (qmail 86078 invoked by uid 99); 28 Oct 2016 21:36:58 -0000 Received: from arcas.apache.org (HELO arcas) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 28 Oct 2016 21:36:58 +0000 Received: from arcas.apache.org (localhost [127.0.0.1]) by arcas (Postfix) with ESMTP id 770BD2C1F56 for ; Fri, 28 Oct 2016 21:36:58 +0000 (UTC) Date: Fri, 28 Oct 2016 21:36:58 +0000 (UTC) From: "Jaimin Jetly (JIRA)" To: issues@ambari.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (AMBARI-18694) DataNode JVM heap settings should include CMSInitiatingOccupancy MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 archived-at: Fri, 28 Oct 2016 21:37:00 -0000 [ https://issues.apache.org/jira/browse/AMBARI-18694?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15616659#comment-15616659 ] Jaimin Jetly commented on AMBARI-18694: --------------------------------------- +1 for the patch > DataNode JVM heap settings should include CMSInitiatingOccupancy > ---------------------------------------------------------------- > > Key: AMBARI-18694 > URL: https://issues.apache.org/jira/browse/AMBARI-18694 > Project: Ambari > Issue Type: Improvement > Affects Versions: 2.2.2 > Reporter: Xiaobing Zhou > Assignee: Xiaobing Zhou > Fix For: 2.5.0 > > Attachments: AMBARI-18694.000.patch, AMBARI-18694.001.patch > > > As HDFS-11047 reported, DirectoryScanner does scan by deep copying FinalizedReplica. In a deployment with 500,000+ blocks, we've seen the DN heap usage being accumulated to high peaks very quickly. Deep copies of FinalizedReplica will make DN heap usage even worse if directory scans are scheduled more frequently. > Another factor is that huge number of ScanInfo instances corresponding to HDFS blocks are lingering in garbage to eat many heap memories until a full GC takes place. > This proposes adding JVM settings to force GC more frequently to release DataNode heap consumed as a result of two aforementioned reasons, i.e. add the options to HADOOP_DATANODE_OPTS > {noformat} > -XX:CMSInitiatingOccupancyFraction=70 -XX:+UseCMSInitiatingOccupancyOnly -XX:ConcGCThreads=8 -XX:+UseConcMarkSweepGC > {noformat} -- This message was sent by Atlassian JIRA (v6.3.4#6332)