Return-Path: X-Original-To: apmail-hadoop-hdfs-issues-archive@minotaur.apache.org Delivered-To: apmail-hadoop-hdfs-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 8E1A017EB5 for ; Fri, 10 Apr 2015 20:48:19 +0000 (UTC) Received: (qmail 57315 invoked by uid 500); 10 Apr 2015 20:48:14 -0000 Delivered-To: apmail-hadoop-hdfs-issues-archive@hadoop.apache.org Received: (qmail 57256 invoked by uid 500); 10 Apr 2015 20:48:14 -0000 Mailing-List: contact hdfs-issues-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: hdfs-issues@hadoop.apache.org Delivered-To: mailing list hdfs-issues@hadoop.apache.org Received: (qmail 57244 invoked by uid 99); 10 Apr 2015 20:48:14 -0000 Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 10 Apr 2015 20:48:14 +0000 Date: Fri, 10 Apr 2015 20:48:14 +0000 (UTC) From: "Arpit Agarwal (JIRA)" To: hdfs-issues@hadoop.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (HDFS-6919) Enforce a single limit for RAM disk usage and replicas cached via locking 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/HDFS-6919?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14490336#comment-14490336 ] Arpit Agarwal commented on HDFS-6919: ------------------------------------- As a first step the memory writer can reserve space for a full replica in FsDatasetCache. The memory will be released if a block is finalized at less than full length or when the block is evicted from ramfs. This gets us towards a unified configuration for both features via {{dfs.datanode.max.locked.memory}}. I looked at the FsDatasetCache code and the change seems easy in theory. Next we could add a hook for CCM to evict ramfs replicas. > Enforce a single limit for RAM disk usage and replicas cached via locking > ------------------------------------------------------------------------- > > Key: HDFS-6919 > URL: https://issues.apache.org/jira/browse/HDFS-6919 > Project: Hadoop HDFS > Issue Type: Bug > Reporter: Arpit Agarwal > Assignee: Arpit Agarwal > > The DataNode can have a single limit for memory usage which applies to both replicas cached via CCM and replicas on RAM disk. > See comments [1|https://issues.apache.org/jira/browse/HDFS-6581?focusedCommentId=14106025&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-14106025], [2|https://issues.apache.org/jira/browse/HDFS-6581?focusedCommentId=14106245&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-14106245] and [3|https://issues.apache.org/jira/browse/HDFS-6581?focusedCommentId=14106575&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-14106575] for discussion. -- This message was sent by Atlassian JIRA (v6.3.4#6332)