order of async requests to zookeeper

2011-12-22 Thread Ted Yu
Hi, The following originated from discussion on a feature in HBase which relies on zookeeper for coordination. A task is removed from the tasks map. An async ZK request is pending to remove the task's zk node. Another request arrives for this to-be-deleted task. A new in-memory task structure is

Re: order of async requests to zookeeper

2011-12-22 Thread Benjamin Reed
are all of these requests being issued from the same zookeeper handle? ben On Thu, Dec 22, 2011 at 6:09 PM, Ted Yu wrote: > Hi, > The following originated from discussion on a feature in HBase which relies > on zookeeper for coordination. > > A task is removed from the tasks map. An async ZK req

Re: order of async requests to zookeeper

2011-12-23 Thread Ted Yu
The requests come from same zhandle. Cheers On Thu, Dec 22, 2011 at 6:09 PM, Ted Yu wrote: > Hi, > The following originated from discussion on a feature in HBase which > relies on zookeeper for coordination. > > A task is removed from the tasks map. An async ZK request is pending to > remove th

Re: order of async requests to zookeeper

2011-12-26 Thread Mahadev Konar
Ted, ZK does not re order async requests. They will be executed in the same order as you call them from the same zk handle. Does that help? thanks mahadev On Fri, Dec 23, 2011 at 10:43 AM, Ted Yu wrote: > The requests come from same zhandle. > > Cheers > > On Thu, Dec 22, 2011 at 6:09 PM, Ted Y

Re: order of async requests to zookeeper

2011-12-26 Thread Ted Yu
Sure. That helps, Mahadev. Can I assume that async requests from different zk handles don't have guaranteed order of execution ? On Mon, Dec 26, 2011 at 4:23 PM, Mahadev Konar wrote: > Ted, > ZK does not re order async requests. They will be executed in the > same order as you call them from th

Re: order of async requests to zookeeper

2011-12-26 Thread Ted Dunning
Well, you have a constraint on the ordering from the ordering for requests from each separate handle. Other than that, it is hard to see how you could get a stronger ordering. On Mon, Dec 26, 2011 at 5:53 PM, Ted Yu wrote: > Sure. > That helps, Mahadev. > > Can I assume that async requests from

Re: order of async requests to zookeeper

2011-12-27 Thread Patrick Hunt
On Mon, Dec 26, 2011 at 5:53 PM, Ted Yu wrote: > Can I assume that async requests from different zk handles don't have > guaranteed order of execution ? Not sure what you mean. There will be _an_ order, and you're guaranteed that all sessions will see the same order. The order will be the order i