Confirmed btw that InterprocessMutex is reaped properly. However locks cannot be reentrant across threads in the same process so I am wondering if I should pull together my own patch from the ticket?
From: David Kesler Sent: Tuesday, March 31, 2015 10:17 AM To: [email protected] How are you constructing your ChildReaper? It sounds like you’re constructing a child reaper using the path of the lock itself and the path the childreaper is watching is getting deleted (though I’m not sure why). If you’re planning on having a number of locks of the form /lock/calendar/uuid1, /lock/calendar/uuid2, etc., you should be creating a single ChildReaper at startup that uses /lock/calendar as the path for your child reaper. This will ensure that the children of /lock/calendar (that is, your uuid locks) will get reaped. You don’t need to be adding /lock/calendar/uuid to your child reaper directly. As a side note, if you’re using InterProcessSemaphoreMutex, there’s currently an issue with ChildReaper in 2.7 (https://issues.apache.org/jira/browse/CURATOR-173) which should hopefully be fixed in the next release. If you can, you may want to consider InterProcessMutex instead. From: [email protected] [mailto:[email protected]] Sent: Tuesday, March 31, 2015 12:57 PM To: [email protected] Subject: Reaper/ChildReaper usage Hi, I’m using the InterProcessSemaphoreMutex for a distributed locking recipe. A typical path for a lock might be /lock/calendar/<uuid> I’d assume these paths need to be cleaned up eventually, so I’ve tried using childreaper and reaper to do so after I unlock the lock. ChildReaper kind of works. If I add /lock/calendar/uuid it happily removes the children. the log shows it removes the leases and locks and the node itself is shown to be gone in zkClient However suddenly it begins complaining in a seemingly endless loop that the path is gone. This despite trying Mode.Delete and Mode.Until Gone. Reaper does nothing, probably because /lock/calendar/uuid has children. Am I missing something? Do I not need to clean up these locks? What do I need to worry concurrency wise about.
