hadoop-hdfs-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Vinayakumar B (JIRA)" <j...@apache.org>
Subject [jira] [Updated] (HDFS-5369) Support negative caching of user-group mapping
Date Thu, 26 Jun 2014 08:17:25 GMT

     [ https://issues.apache.org/jira/browse/HDFS-5369?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Vinayakumar B updated HDFS-5369:
--------------------------------

    Assignee: Lei (Eddy) Xu
      Status: Patch Available  (was: Open)

Submitting patch for [~eddyxu]

> Support negative caching of user-group mapping
> ----------------------------------------------
>
>                 Key: HDFS-5369
>                 URL: https://issues.apache.org/jira/browse/HDFS-5369
>             Project: Hadoop HDFS
>          Issue Type: Improvement
>          Components: namenode
>    Affects Versions: 2.2.0
>            Reporter: Andrew Wang
>            Assignee: Lei (Eddy) Xu
>         Attachments: HDFS-5369.000.patch
>
>
> We've seen a situation at a couple of our customers where interactions from an unknown
user leads to a high-rate of group mapping calls. In one case, this was happening at a rate
of 450 calls per second with the shell-based group mapping, enough to severely impact overall
namenode performance and also leading to large amounts of log spam (prints a stack trace each
time).
> Let's consider negative caching of group mapping, as well as quashing the rate of this
log message.



--
This message was sent by Atlassian JIRA
(v6.2#6252)

Mime
View raw message