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Zookeeper >> mail # user >> lost ZK events across datacenters


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Re: lost ZK events across datacenters
yes, the LogFormatter class will do it for me.

ben

On Wed, Jun 8, 2011 at 1:55 PM, Jun Rao <[EMAIL PROTECTED]> wrote:
> Ben,
>
> The log is binary. Is there a log reader? Also, can I just look at the log
> on any zookeeper server?
>
> Thanks,
>
> Jun
>
> On Fri, Jun 3, 2011 at 10:18 AM, Benjamin Reed <[EMAIL PROTECTED]> wrote:
>
>> actually, i think the transaction log could help a lot, and that will
>> always be there. two scenarios i can think of are:
>> 1) the change happened before the watch was set
>> 2) the change never got there
>> you could get an answer to both of those questions by looking at the
>> transaction log.
>>
>> ben
>>
>> On Fri, Jun 3, 2011 at 9:59 AM, Jun Rao <[EMAIL PROTECTED]> wrote:
>> > I don't expect that we can discover the problem right now. However, what
>> are
>> > the things that I can do to collect enough tracing should the problem
>> occur
>> > again in the future (e.g., is INFO level logging enough)?
>> >
>> > Thanks,
>> >
>> > Jun
>> >
>> > On Fri, Jun 3, 2011 at 9:56 AM, Jun Rao <[EMAIL PROTECTED]> wrote:
>> >
>> >> The log doesn't have any state changing entries around the time the
>> watcher
>> >> is triggered, in all clients.
>> >>
>> >> Jun
>> >>
>> >>
>> >> On Fri, Jun 3, 2011 at 9:32 AM, Fournier, Camille F. [Tech] <
>> >> [EMAIL PROTECTED]> wrote:
>> >>
>> >>> Any state changes for the problem client between setting the watch and
>> >>> when you expected it to get called? Do you have logs for that client vs
>> the
>> >>> others that show anything?
>> >>>
>> >>> -----Original Message-----
>> >>> From: Jun Rao [mailto:[EMAIL PROTECTED]]
>> >>> Sent: Friday, June 03, 2011 4:40 AM
>> >>> To: [EMAIL PROTECTED]
>> >>> Subject: Re: lost ZK events across datacenters
>> >>>
>> >>> Ben,
>> >>>
>> >>> Some details below.
>> >>>
>> >>> The call that sets the watcher simple calls getChildren with watcher
>> flag
>> >>> set to true. The triggering change is that one of the child nodes
>> (which
>> >>> is
>> >>> ephemeral) is deleted because the creating client is gone.
>> >>>
>> >>> Thanks,
>> >>>
>> >>> Jun
>> >>>
>> >>> On Thu, Jun 2, 2011 at 10:49 AM, Benjamin Reed <[EMAIL PROTECTED]>
>> wrote:
>> >>>
>> >>> > can you tell us a bit more about the scenario? what was the call the
>> >>> > set the watch event? and what were the changes that caused the event?
>> >>> >
>> >>> > thanx
>> >>> > ben
>> >>> >
>> >>> > On Wed, Jun 1, 2011 at 3:14 PM, Jun Rao <[EMAIL PROTECTED]> wrote:
>> >>> > > All my clients were on different machines. 2 of them got the
>> watcher
>> >>> > fired
>> >>> > > about the same time. The third one never got the watcher triggered.
>> >>> > >
>> >>> > > Thanks,
>> >>> > >
>> >>> > > Jun
>> >>> > >
>> >>> > > On Wed, Jun 1, 2011 at 2:18 PM, Fournier, Camille F. [Tech] <
>> >>> > > [EMAIL PROTECTED]> wrote:
>> >>> > >
>> >>> > >> All clients are in different processes?
>> >>> > >> I've used zkclient and haven't seen any problems, but I haven't
>> >>> hammered
>> >>> > it
>> >>> > >> too hard yet. I took a long look at the code and didn't see any
>> >>> errors
>> >>> > but
>> >>> > >> there could always be something very subtle.
>> >>> > >>
>> >>> > >> -----Original Message-----
>> >>> > >> From: Jun Rao [mailto:[EMAIL PROTECTED]]
>> >>> > >> Sent: Wednesday, June 01, 2011 4:09 PM
>> >>> > >> To: [EMAIL PROTECTED]
>> >>> > >> Subject: Re: lost ZK events across datacenters
>> >>> > >>
>> >>> > >> I am using the zkclient package (
>> >>> > >> https://github.com/sgroschupf/zkclient.git).
>> >>> > >> The watcher code seems reasonable. Basically, each watcher event
>> is
>> >>> > first
>> >>> > >> added to a queue. A separate event thread dequeues each event and
>> >>> reads
>> >>> > the
>> >>> > >> children of a path (which re-registers the watcher) and invokes
>> the
>> >>> > >> registered listener.
>> >>> > >>
>> >>> > >> Anybody knows any issues in zkclient?
>> >>> > >>
>> >>> > >> Thanks,
>> >>> > >>
>> >>> > >> Jun
>> >>> > >>
>> >>> > >> On Wed, Jun 1, 2011 at 12:04 PM, Ted Dunning <