Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Threaded View
Kafka >> mail # user >> Understanding how to monitor using JMX attributes


Copy link to this message
-
Re: Understanding how to monitor using JMX attributes
Mike,

I'm not sure the Storm-bundled kafka stores offsets in the same ZK
locations as the regular Kafka consumer.     Actually if you can verify the
location that would be great, cuz I'm curious.   Anyways the
ConsumerOffsetChecker would not be able to help if the ZK locations were
different.

-Evan

On Tue, Nov 20, 2012 at 8:03 AM, Mike Heffner <[EMAIL PROTECTED]> wrote:

> I have not tried that yet, I was hoping to use an existing Ruby monitoring
> process that we use to monitor several other existing resources.  I also
> don't want to make changes to the Kafka consumer code, as it's part of a
> bundled package (Storm).
>
> Where does ConsumerOffsetChecker pull its information from? Shouldn't the
> values from JMX match? Guess I might need to look at its source code to
> figure out what it's doing.
>
>
>
>
> On Tue, Nov 20, 2012 at 12:34 AM, Jun Rao <[EMAIL PROTECTED]> wrote:
>
> > Instead of using jmx, have you tried using ConsumerOffsetChecker to
> figure
> > out the consumer lag?
> >
> > Thanks,
> >
> > Jun
> >
> > On Mon, Nov 19, 2012 at 7:10 PM, Mike Heffner <[EMAIL PROTECTED]> wrote:
> >
> > > Hi,
> > >
> > > I am trying to write a custom monitoring script for our Kafka setup and
> > > would like some help understanding how to interpret the JMX attributes.
> > >
> > > In our setup, the consumers are writing their current offset to a path
> in
> > > ZK. This is the value they are getting back from a call
> > > to SimpleConsumer.getOffsetsBefore(). A snapshot of this value looks
> > like:
> > >
> > > {"offset"=>5338008447, "partition"=>2, "broker"=>{"host"=>"10.x.x.94",
> > > "port"=>9092}, "topic"=>"mcommits"}
> > >
> > > Using the MX4J interface, I poll the
> > > bean "kafka:type=kafka.logs.mcommits-2" on host 10.x.x.94 and get the
> > > attribute values:
> > >
> > > {"CurrentOffset"=>506171524, "Name"=>"mcommits-2",
> > > "NumAppendedMessages"=>10526508, "NumberOfSegments"=>4,
> > "Size"=>2116784530}
> > >
> > > At the time both of these values were snapshotted, this consumer was
> > close
> > > to the end of the log file. In that case, I would expect both offsets
> to
> > be
> > > fairly similar, however the consumer offset is >> the producer log
> > offset,
> > > which doesn't make sense.
> > >
> > > Clearly there is something I'm not understanding. How do I use the JMX
> > > attributes to calculate how far behind the consumer is from the end of
> > the
> > > log file? In this scenario the consumer offset is >> both the
> > CurrentOffset
> > > value and the Size value. Is there a way of interpreting these values
> > that
> > > I'm not seeing?
> > >
> > >
> > > Thanks,
> > >
> > > Mike
> > >
> > > --
> > >
> > >   Mike Heffner <[EMAIL PROTECTED]>
> > >   Librato, Inc.
> > >
> >
>
>
>
> --
>
>   Mike Heffner <[EMAIL PROTECTED]>
>   Librato, Inc.
>

--
--
*Evan Chan*
Senior Software Engineer |
[EMAIL PROTECTED] | (650) 996-4600
www.ooyala.com | blog <http://www.ooyala.com/blog> |
@ooyala<http://www.twitter.com/ooyala>