When processing edits log, quota verification is not done and the used quota for directories is not updated. The update is done at the end of processing edits log. This rule is broken by change introduced in
HDFS-677. This causes namenode from handling rename operation from edits log due to quota verification failure. Once this happens, namenode does not proceed edits log any further. This results in check point failure on backup node or secondary namenode. This also prevents namenode from coming up.