Thanks for your response. Yes I think the issue referred to in CURATOR-173 
might be the problem


because I have tried adding /lock/calendar itself, and the child 
/lock/calendar/uuid does NOT get removed (probably because it itself has 
children).








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.

Reply via email to