You are viewing a plain text version of this content. The canonical link for it is here.
Posted to common-issues@hadoop.apache.org by "zhoutai.zt (JIRA)" <ji...@apache.org> on 2017/11/07 07:37:00 UTC
[jira] [Updated] (HADOOP-15020) NNBench not support run more than
one map task on the same host
[ https://issues.apache.org/jira/browse/HADOOP-15020?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
zhoutai.zt updated HADOOP-15020:
--------------------------------
Summary: NNBench not support run more than one map task on the same host (was: NNBench not support run more than one map task on one host)
> NNBench not support run more than one map task on the same host
> ---------------------------------------------------------------
>
> Key: HADOOP-15020
> URL: https://issues.apache.org/jira/browse/HADOOP-15020
> Project: Hadoop Common
> Issue Type: Improvement
> Components: benchmarks
> Affects Versions: 2.7.2
> Environment: Hadoop 2.7.2
> Reporter: zhoutai.zt
> Priority: Minor
>
> When benchmark NameNode performance with NNBench. I start with pseudo distributed deploy. Everything goes well with "-maps 1". BUT with -maps N (n>1) and -operation create_write, many exceptions meet during the benchmark.
> Hostname is part of the file path, which can differentiate hosts. With more than two map tasks run on the same host, more than two map tasks may operate on the same file, leading to exceptions.
> 17/11/07 15:22:32 INFO hdfs.NNBench: RAW DATA: AL Total #1: 84
> 17/11/07 15:22:32 INFO hdfs.NNBench: RAW DATA: AL Total #2: 43
> 17/11/07 15:22:32 INFO hdfs.NNBench: RAW DATA: TPS Total (ms): 2570
> 17/11/07 15:22:32 INFO hdfs.NNBench: RAW DATA: Longest Map Time (ms): 814.0
> 17/11/07 15:22:32 INFO hdfs.NNBench: RAW DATA: Late maps: 0
> 17/11/07 15:22:32 INFO hdfs.NNBench: {color:red}RAW DATA: # of exceptions: 3000{color}
> 2017-11-07 14:54:08,082 INFO org.apache.hadoop.hdfs.NNBench: Exception recorded in op: Create/Write/Close
> 2017-11-07 14:54:08,082 INFO org.apache.hadoop.hdfs.NNBench: Exception recorded in op: Create/Write/Close
> 2017-11-07 14:54:08,083 INFO org.apache.hadoop.hdfs.NNBench: Exception recorded in op: Create/Write/Close
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
---------------------------------------------------------------------
To unsubscribe, e-mail: common-issues-unsubscribe@hadoop.apache.org
For additional commands, e-mail: common-issues-help@hadoop.apache.org