[ https://issues.apache.org/jira/browse/HDFS-16439?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
ASF GitHub Bot updated HDFS-16439: ---------------------------------- Labels: pull-request-available (was: ) > Makes calculating maxNodesPerRack simpler > ----------------------------------------- > > Key: HDFS-16439 > URL: https://issues.apache.org/jira/browse/HDFS-16439 > Project: Hadoop HDFS > Issue Type: Improvement > Components: namenode > Affects Versions: 3.4.0 > Reporter: JiangHua Zhu > Assignee: JiangHua Zhu > Priority: Major > Labels: pull-request-available > Time Spent: 10m > Remaining Estimate: 0h > > When creating a new file, it is usually necessary to communicate with the > namenode first to obtain the location of some DataNodes as the target > location of Blockd. At this time, when > BlockPlacementPolicyDefault#getMaxNodesPerRack() is executed, if the number > of replicas is very large, once it exceeds the number of all nodes in the > cluster. The following piece of code will be executed: > int clusterSize = clusterMap.getNumOfLeaves(); > int totalNumOfReplicas = numOfChosen + numOfReplicas; > if (totalNumOfReplicas > clusterSize) { > numOfReplicas -= (totalNumOfReplicas-clusterSize); > totalNumOfReplicas = clusterSize; > } > Here, the calculation for numOfReplicas gets a little more complicated. It > can be simplified like: > numOfReplicas = clusterSize - numOfChosen > It would be more helpful to understand it this way, while also freeing up a > little cpu (though not a lot). -- This message was sent by Atlassian Jira (v8.20.1#820001) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org