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Zookeeper >> mail # dev >> order of async requests to zookeeper


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Re: order of async requests to zookeeper
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 <[EMAIL PROTECTED]> wrote:

> 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 <[EMAIL PROTECTED]
> >wrote:
>
> > 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 <[EMAIL PROTECTED]> wrote:
> > > The requests come from same zhandle.
> > >
> > > Cheers
> > >
> > > On Thu, Dec 22, 2011 at 6:09 PM, Ted Yu <[EMAIL PROTECTED]> 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 the task's zk node.
> > >>
> > >>  Another request arrives for this to-be-deleted task. A new in-memory
> > >> task structure is created. A ZK request is scheduled to create the
> same
> > >> task node.
> > >>
> > >>  Problem will only occur if create-node executes before delete-node in
> > >> ZK. (If create-node returns NODEEXISTS then we treat that as success).
> > >>
> > >> Does ZK re-order async requests?
> > >>
> > >> Thanks
> > >>
> >
>