[jira] [Assigned] (HDFS-7501) TransactionsSinceLastCheckpoint can be negative on SBNs
[ https://issues.apache.org/jira/browse/HDFS-7501?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Stephen Chu reassigned HDFS-7501: - Assignee: Stephen Chu 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: Stephen Chu Priority: Trivial 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)
[jira] [Assigned] (HDFS-7501) TransactionsSinceLastCheckpoint can be negative on SBNs
[ https://issues.apache.org/jira/browse/HDFS-7501?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Gautam Gopalakrishnan reassigned HDFS-7501: --- Assignee: Gautam Gopalakrishnan (was: Stephen Chu) 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 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)
