Are you using a JVM language? Curator already has a revocable lock recipe. http://curator.apache.org/apidocs/org/apache/curator/framework/recipes/locks/InterProcessMutex.html
-Jordan On Dec 15, 2013, at 8:28 AM, mdzfirst mdzfirst <[email protected]> wrote: > Hi everyone, > > I would like to implement a 'preemptible' mutex with the WriteLock example > in the recipe. My method is like this. > > 1. Acquire the WriteLock and get the resources > 2. Set a watch on the lock's root node with getChildren() repeatedly, using > a separate ZooKeeper client > 3. If only one child (self) is found, sleep > 4. The callback function only wakes up the main thread > 5. If the watch is triggered and > 1 children are found, release the > resources and unlock the WriteLock > > In my design, I will execute the jar multiple times. Each time a new one is > started, the old one should be forced to release the mutex. It works. The > first execution does stop. However, the second process seems to lose its > watch on the first one, because the callback function I passed to the > WriteLock object is never evoked. The callback function is used to > synchronize the locking request and is thus very important. > > Can anyone see any flaws in my design, or provide a different way that > works? Thanks~ > > Best regards, > mdzfirst
