[
https://issues.apache.org/jira/browse/HDFS-6154?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Fengdong Yu updated HDFS-6154:
------------------------------
Assignee: (was: Fengdong Yu)
> Improve the speed of saveNameSpace，making HDFS restart and checkPoint faster
> ----------------------------------------------------------------------------
>
> Key: HDFS-6154
> URL: https://issues.apache.org/jira/browse/HDFS-6154
> Project: Hadoop HDFS
> Issue Type: Improvement
> Affects Versions: 2.3.0
> Reporter: guodongdong
> Attachments: HDFS-6154-patch
>
>
> There are two stage In namenode savenamespace, serializing INode, calculate
> MD5 and write to disk. Now, two stage is doing serially, In this
> improvement, it is doing parallel, one thread do serializing INode, other
> thread do calculating MD5 and writing to disk, it double speed of
> savenamespace, Detail is show in table:
> Testing environment:
> only test namenode savenamespace, dfsadmin -saveNamespace
> machine: 144GB, Intel(R) Xeon(R) CPU E5645 @ 2.40GHz, 12 cpu, Raid 5
> SAS Disk, jdk 1.7.0
>
> ||image size||before optimizing||after optimizing ||
> |1.2GB|22sec|11sec|
> |4.3GB|66sec|36sec|
> |22GB|406sec|250sec|
--
This message was sent by Atlassian JIRA
(v6.2#6252)
