No it's the age in ms:

ageOfLastAppliedOp.set(System.currentTimeMillis() - timestamp);

And the timestamp is the one given to the HLogEdit, not the timestamp
of the cell.

J-D

On Thu, Mar 3, 2011 at 11:13 AM, Otis Gospodnetic
<[email protected]> wrote:
> Is that really the *age* really the *timestamp* of last successful log 
> shipment?
> If so, one could calculate the real age with age = now() -
> ageOfLastShippedOnWhichIsReallyTimestamp .  And that would be useful to have.
>
> Otis
> ----
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>
>
>
> ----- Original Message ----
>> From: Jean-Daniel Cryans <[email protected]>
>> To: [email protected]
>> Sent: Thu, March 3, 2011 12:21:09 PM
>> Subject: Re: Questions about HBase Cluster Replication
>>
>> It's a work in progress, that information is currently published by
>> every  region server in the master cluster (since it's push
>> replication, not pull)  through JMX under the name
>> "ageOfLastShippedOp". It's really not perfect  though, since if it
>> fails to replicate and starts retrying then the age won't  change but
>> the actual lag will go up. Also it will have to be revisited when  we
>> add multiple slaves since you don't really want to publish the  same
>> metric for multiple slaves... it really wouldn't  work.
>>
>> J-D
>>
>> On Thu, Mar 3, 2011 at 9:10 AM, Bill Graham <[email protected]> wrote:
>> >  Actually, how far behind replication is w.r.t. edit logs is different
>> >  than how out of sync they are, but you get the idea.
>> >
>> > On Thu, Mar  3, 2011 at 9:07 AM, Bill Graham <[email protected]>  wrote:
>> >> One more question for the FAQ:
>> >>
>> >> 6. Is  it possible for an admin to tell just how out of sync the two
>> >>  clusters are? Something like Seconds_Behind_Master in MySQL's SHOW
>> >>  SLAVE STATUS?
>> >>
>> >>
>> >> On Wed, Mar 2, 2011 at 9:32  PM, Jean-Daniel Cryans <[email protected]>
>>wrote:
>> >>> Although, I would add that this feature is still  experimental so who 
>> >>> knows
>>:)
>> >>>
>> >>> I think the worst  that happened to us was that replication was broken
>> >>> (see the  jira where if the master loses it's zk session with the slave
>> >>> zk  ensemble, it requires a HBase restart on the master side) for a  few
>> >>> days because of maintenance of the link between the two  datacenters
>> >>> which took more than a minute. When we finally did  restart the master
>> >>> cluster, it had to process about 2TBs of  HLogs... those ICVs can
>> >>> really generate a lot of  data!
>> >>>
>> >>> J-D
>> >>>
>> >>> On  Wed, Mar 2, 2011 at 9:25 PM, Jean-Daniel Cryans <[email protected]>
>>wrote:
>> >>>>> 5. If one is adding replication on the  *production* Master cluster,
>>what's the
>> >>>>> worst thing that  can happen to this Master cluster?  Nothing scary 
>> >>>>> other
>>than
>> >>>>> changing configs + interruption during a restart?  (which is currently
>>still bad
>> >>>>> because of region  assignments?)
>> >>>>>
>> >>>>
>> >>>>  The replication code is pretty much encapsulated from the rest of  the
>> >>>> region server code, it won't mess with your Puts or  change your
>> >>>> birthday  date.
>> >>>>
>> >>>> With 0.90 the regions are  reassigned where they were before, so it's
>> >>>> really just the  block cache that gets screwed.
>> >>>>
>> >>>>  J-D
>> >>>>
>> >>>
>> >>
>> >
>>
>

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