Add a block counter to DatanodeDescriptor -----------------------------------------
Key: HDFS-1368 URL: https://issues.apache.org/jira/browse/HDFS-1368 Project: Hadoop HDFS Issue Type: Improvement Components: name-node Reporter: Hairong Kuang Assignee: Hairong Kuang Fix For: 0.22.0 Many of time, we need to count the total number of blocks in a datanode by calling DatanodeDescriptor#numBlocks(). It has to traverse the block list to get the counter, which may not be trivial if there are millions of blocks. Adding a counter for each datanode does not cost much space but help save CPU processing time. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.