[ https://issues.apache.org/jira/browse/HDFS-6154?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
guodongdong updated HDFS-6154: ------------------------------ Attachment: (was: HDFS-6154-new-patch) > 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)