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 A63B3176AE for ; Wed, 25 Mar 2015 00:39:57 +0000 (UTC) Received: (qmail 66252 invoked by uid 500); 25 Mar 2015 00:39:57 -0000 Delivered-To: apmail-hadoop-hdfs-issues-archive@hadoop.apache.org Received: (qmail 66201 invoked by uid 500); 25 Mar 2015 00:39:57 -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 66187 invoked by uid 99); 25 Mar 2015 00:39:57 -0000 Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 25 Mar 2015 00:39:57 +0000 Date: Wed, 25 Mar 2015 00:39:57 +0000 (UTC) From: "Gautam Gopalakrishnan (JIRA)" To: hdfs-issues@hadoop.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (HDFS-7501) TransactionsSinceLastCheckpoint can be negative on SBNs 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-7501?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14379024#comment-14379024 ] Gautam Gopalakrishnan commented on HDFS-7501: --------------------------------------------- Thanks Harsh, sorry I couldn't get to this earlier. > TransactionsSinceLastCheckpoint can be negative on SBNs > ------------------------------------------------------- > > Key: HDFS-7501 > URL: https://issues.apache.org/jira/browse/HDFS-7501 > Project: Hadoop HDFS > Issue Type: Bug > Components: namenode > Affects Versions: 2.5.0 > Reporter: Harsh J > Assignee: Gautam Gopalakrishnan > Priority: Trivial > Attachments: HDFS-7501-2.patch, HDFS-7501-3.patch, HDFS-7501.patch > > > The metric TransactionsSinceLastCheckpoint is derived as FSEditLog.txid minus NNStorage.mostRecentCheckpointTxId. > In Standby mode, the former does not increment beyond the loaded or last-when-active value, but the latter does change due to checkpoints done regularly in this mode. Thereby, the SBN will eventually end up showing negative values for TransactionsSinceLastCheckpoint. > This is not an issue as the metric only makes sense to be monitored on the Active NameNode, but we should perhaps just show the value 0 by detecting if the NN is in SBN form, as allowing a negative number is confusing to view within a chart that tracks it. -- This message was sent by Atlassian JIRA (v6.3.4#6332)