On Tue, Jan 4, 2011 at 7:03 AM, Mohit <mohitsi...@huawei.com> wrote: > Hello All, > > > > What is the purpose of maintaining hive history files which contain session > information like session start, query start, query end, task start, task end > etc.? Are they being used later (say by a tool) for some purpose? > > > > I don't see these files being getting deleted from the system ;any > configuration needed to be set to enable deletion or Is there any design > strategy/decision/rationale for not deleting them at all? > > > > Also, in these files I don't see the session end message being logged, is it > reserved for future use? > > > > -Mohit > > > > *************************************************************************************** > This e-mail and attachments contain confidential information from HUAWEI, > which is intended only for the person or entity whose address is listed > above. Any use of the information contained herein in any way (including, > but not limited to, total or partial disclosure, reproduction, or > dissemination) by persons other than the intended recipient's) is > prohibited. If you receive this e-mail in error, please notify the sender by > phone or email immediately and delete it! > >
HiveHistory was added a while ago between 3.0 and 4.0 (iirc). A tool to view them is HiveHistoryViewer in the API. I am not exactly sure who is doing what with that data. The Web Interface does use it to provide links to the JobTracker. So it helpful for trying to trace all the dependant jobs of a query after the fact. There is a ticket open to customize the file location. I was also thinking we should allow the user to supply a 'none' to turn off the feature. As for clean up and management cron and rm seem like a good fit.
