Speedup NameNode image loading and saving
-----------------------------------------
Key: HDFS-1070
URL: https://issues.apache.org/jira/browse/HDFS-1070
Project: Hadoop HDFS
Issue Type: Improvement
Components: name-node
Reporter: Hairong Kuang
Assignee: Hairong Kuang
Fix For: 0.22.0
Currently each inode stores its full path in the fsimage. I'd propose to store
the local name instead. In order for each inode to identify its parent, all
inodes in a directory tree are stored in the image in in-order. This proposal
also requires each directory stores the number of its children in image.
This proposal would bring a few benefits as pointed below and therefore speedup
the image loading and saving.
1. Remove the overhead of converting java-UTF8 encoded local name to
string-represented full path then to UTF8 encoded full path when saving to
image and vice versa when loading the image.
2. Remove the overhead of traversing the full path when inserting the inode to
its parent inode.
2. Reduce the number of temporary java objects during the process of image
loading or saving and therefore reduce the GC overhead.
3. Reduce the size of image.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
