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Allen Wittenauer commented on HADOOP-1869: ------------------------------------------ Now that we have permissions and ownerships, such an access log would also need to differentiate between reads, writes, ownership changes, and permission changes. This would be _extremely_ helpful in case forensics need to be performed to track down someone doing Bad Things(tm). > access times of HDFS files > -------------------------- > > Key: HADOOP-1869 > URL: https://issues.apache.org/jira/browse/HADOOP-1869 > Project: Hadoop > Issue Type: New Feature > Components: dfs > Reporter: dhruba borthakur > > HDFS should support some type of statistics that allows an administrator to > determine when a file was last accessed. > Since HDFS does not have quotas yet, it is likely that users keep on > accumulating files in their home directories without much regard to the > amount of space they are occupying. This causes memory-related problems with > the namenode. > Access times are costly to maintain. AFS does not maintain access times. I > thind DCE-DFS does maintain access times with a coarse granularity. > One proposal for HDFS would be to implement something like an "access bit". > 1. This access-bit is set when a file is accessed. If the access bit is > already set, then this call does not result in a transaction. > 2. A FileSystem.clearAccessBits() indicates that the access bits of all files > need to be cleared. > An administrator can effectively use the above mechanism (maybe a daily cron > job) to determine files that are recently used. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.