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Kafka >> mail # user >> Broker rejoin with big replica lag


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Re: Broker rejoin with big replica lag
Deleting topic is an on-going JIRA: KAFKA-330, and we are shooting for have
it checked in soon.
On Wed, Feb 5, 2014 at 3:59 PM, David Birdsong <[EMAIL PROTECTED]>wrote:

> On Wed, Feb 5, 2014 at 2:22 PM, Robert Rodgers <[EMAIL PROTECTED]>
> wrote:
>
> > this would be great to add to the operational section of the Kafka
> > documentation.
> >
>
> So is this a way to delete topics? Does this work?
>
>
>
> >
> > On Feb 5, 2014, at 2:18 PM, Andrew Otto <[EMAIL PROTECTED]> wrote:
> >
> > >> - Increasing num.replica.fetchers (defaults is one)
> > > Awesome!  I just tried this one, bumped it up to 8 (12 cores on this
> > broker box).  It is now catching up at around 17K msgs/sec, which will
> mean
> > it will finish in about 4 or 5 hours.  I'll check up on it again
> tomorrow.
> > >
> > > That should do it,  Thanks!
> > >
> > >
> > >
> > > On Feb 5, 2014, at 5:04 PM, Joel Koshy <[EMAIL PROTECTED]> wrote:
> > >
> > >>
> > >>> topics are all caught up, but I have one high volume topic (around
> > >>> 40K msgs/sec) that is taking much longer.  I just took a few samples
> > >>> of Replica-MaxLag to see how long it would take to catch up.
> > >>> Currently, it is behind about 12.5 million messages and is catching
> > >>> up at a rate of about 1600 msgs/sec.  At that rate, it'll take
> > >>> around 9 days before the replica is caught up to the leader.
> > >>>
> > >>> Is there any way to speed this up?
> > >>
> > >> During the period your high-volume topic is under-replicated you can
> > >> temporarily try one or both of the following:
> > >> - Increasing num.replica.fetchers (defaults is one)
> > >> - If you don't have too many topic-partitions you can also increase
> > >> replica.fetch.max.bytes.
> > >>
> > >>> Or, alternatively, I don't actually care about this topic's
> > >>> history.  It is a new topic, and I know that it doesn't yet have any
> > >>> consumers.  I'd be fine with instructing both brokers to drop
> > >>> old logs and just start from the top of the log.  I could do this by
> > >>> manually deleting the topic (kafka data files and in zookeeper), but
> > >>> to do so properly with 0.8.0 I think I'd have to shut down the
> > >>> whole cluster, correct?  I'd rather not do this, as another
> > >>> topic does have a consumer and I don't want to lose messages for
> > >>> it.
> > >>
> > >> Right - or you could do a rolling bounce and change the retention
> > >> settings (http://kafka.apache.org/documentation.html#brokerconfigs)
> of
> > >> that topic to something low so it gets expired and then do another
> > >> rolling bounce to remove the override.
> > >>
> > >> --
> > >> Joel
> > >
> >
> >
>

--
-- Guozhang