Mingliang Liu created HDFS-9379: ----------------------------------- Summary: Make NNThroughputBenchmark support more than 10 numThreads Key: HDFS-9379 URL: https://issues.apache.org/jira/browse/HDFS-9379 Project: Hadoop HDFS Issue Type: Improvement Components: namenode Reporter: Mingliang Liu Assignee: Mingliang Liu
Currently, the {{NNThroughputBenchmark}} relies on sorted {{datanodes}} array in the lexicographical order of datanode's {{xferAddr}}. * There is an assertion of datanode's {{xferAddr}} lexicographical order when filling the {{datanodes}}, see [the code|https://github.com/apache/hadoop/blob/trunk/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/NNThroughputBenchmark.java#L1152]. * When searching the datanode by {{DatanodeInfo}}, it uses binary search against the {{datanodes}} array, see [the code|https://github.com/apache/hadoop/blob/trunk/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/NNThroughputBenchmark.java#L1187] In {{DatanodeID}}, the {{xferAddr}} is defined as {{host:port}}. In {{NNThroughputBenchmark}}, the port is simply _the index of the tiny datanode_ plus one. The problem here is that, when there are more than 9 tiny datanodes ({{numThreads}}), the lexicographical order of datanode's {{xferAddr}} will be invalid as the string value of datanode index is not in lexicographical order any more. For example, {code} ... 192.168.54.40:8 192.168.54.40:9 192.168.54.40:10 192.168.54.40:11 ... {code} {{192.168.54.40:9}} is greater than {{192.168.54.40:10}}. The assertion will fail and the binary search won't work. The simple fix is to calculate the datanode index by port directly, instead of using binary search. -- This message was sent by Atlassian JIRA (v6.3.4#6332)