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Koji Noguchi commented on HADOOP-1463: -------------------------------------- > if we want the latter, Yes I prefer the latter. (Datanode utilizing another 10G of space) As a side note, we might want to update the config description for "dfs.datanode.du.pct". It seems to be different from what it actually does. <property> <name>dfs.datanode.du.pct</name> <value>0.98f</value> <description>When calculating remaining space, only use this percentage of the real available space </description> </property> > dfs should report total size of all the space that dfs is using > --------------------------------------------------------------- > > Key: HADOOP-1463 > URL: https://issues.apache.org/jira/browse/HADOOP-1463 > Project: Hadoop > Issue Type: Improvement > Components: dfs > Affects Versions: 0.12.3 > Reporter: Hairong Kuang > Fix For: 0.14.0 > > > Currently namenode reports two statistics back to the client: > 1. The total capacity of dfs. This is a sum of all datanode's capacities, > each of which is calculated by datanode summing all data directories disk > space. > 2. The total remaining space of dfs. This is a sum of all datanodes's > remaining space. Each datanode's remaining space is calculated by using the > following formula: remaining space = unused space - > capacity*unusableDiskPercentage - reserved space. So the remaining space > shows how much space that the dfs can still use, but it does not show the > size of unused space. > Each dfs client caculates the total dfs used space by substracting remaining > space from the total capacity. So the used space does not accurately shows > the space that dfs is using. However it is a very important number that dfs > should provide. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.