Return-Path: X-Original-To: apmail-hadoop-common-issues-archive@minotaur.apache.org Delivered-To: apmail-hadoop-common-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 0B01F11BB9 for ; Thu, 26 Jun 2014 17:23:28 +0000 (UTC) Received: (qmail 50129 invoked by uid 500); 26 Jun 2014 17:23:27 -0000 Delivered-To: apmail-hadoop-common-issues-archive@hadoop.apache.org Received: (qmail 50088 invoked by uid 500); 26 Jun 2014 17:23:27 -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 50033 invoked by uid 99); 26 Jun 2014 17:23:27 -0000 Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 26 Jun 2014 17:23:27 +0000 Date: Thu, 26 Jun 2014 17:23:27 +0000 (UTC) From: "Lei (Eddy) Xu (JIRA)" To: common-issues@hadoop.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Updated] (HADOOP-10755) Support negative caching of user-group mapping 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-10755?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Lei (Eddy) Xu updated HADOOP-10755: ----------------------------------- Attachment: HADOOP-10755.000.patch This patch changes default value of negative cache timeout to 30 seconds. Also it changes the configuration key of negative cache timeout as "negative-cache.secs". [~vinayrpet] Thank you for the comments! I have one more question: should negative cache be enabled by default? > Support negative caching of user-group mapping > ---------------------------------------------- > > Key: HADOOP-10755 > URL: https://issues.apache.org/jira/browse/HADOOP-10755 > Project: Hadoop Common > Issue Type: Improvement > Components: security > Affects Versions: 2.2.0 > Reporter: Andrew Wang > Assignee: Lei (Eddy) Xu > Attachments: HADOOP-10755.000.patch, HDFS-5369.000.patch > > > We've seen a situation at a couple of our customers where interactions from an unknown user leads to a high-rate of group mapping calls. In one case, this was happening at a rate of 450 calls per second with the shell-based group mapping, enough to severely impact overall namenode performance and also leading to large amounts of log spam (prints a stack trace each time). > Let's consider negative caching of group mapping, as well as quashing the rate of this log message. -- This message was sent by Atlassian JIRA (v6.2#6252)