You are viewing a plain text version of this content. The canonical link for it is here.
Posted to hdfs-dev@hadoop.apache.org by "Yi Liu (JIRA)" <ji...@apache.org> on 2014/08/19 10:19:19 UTC
[jira] [Created] (HDFS-6871) Improve NameNode performance when
creating file
Yi Liu created HDFS-6871:
----------------------------
Summary: Improve NameNode performance when creating file
Key: HDFS-6871
URL: https://issues.apache.org/jira/browse/HDFS-6871
Project: Hadoop HDFS
Issue Type: Improvement
Components: namenode, performance
Reporter: Yi Liu
Assignee: Yi Liu
Priority: Critical
Fix For: 2.6.0
Creating file with overwrite flag will cause NN fall into flush edit logs and block other requests if the file exists.
When we create a file with overwrite flag (default is true) in HDFS, NN will remove original file if it exists. In FSNamesystem#startFileInternal, NN already holds the write lock, it calls {{deleteInt}} if the file exists, there is logSync in {{deleteInt}}. So in this case, logSync is under write lock, it will heavily affect the NN performance.
We should ignore the force logSync in {{deleteInt}} in this case.
--
This message was sent by Atlassian JIRA
(v6.2#6252)