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Sanjay Radia commented on HDFS-1070: ------------------------------------ Hairong, could add a short design doc (say 1 page). Are inode numbers persisted? > Speedup NameNode image loading and saving by storing local file names > --------------------------------------------------------------------- > > 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 > > Attachments: trunkLocalNameImage.patch > > > 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. > # Remove the overhead of converting java-UTF8 encoded local name to > string-represented full path then to UTF8 encoded full path when saving to an > image and vice versa when loading the image. > # Remove the overhead of traversing the full path when inserting the inode to > its parent inode. > # Reduce the number of temporary java objects during the process of image > loading or saving and therefore reduce the GC overhead. > # Reduce the size of an image. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.