Thanks Neha, btw have you seen this exception. We didn't restart any
service it happens in deep night.
java.lang.RuntimeException: A broker is already registered on the path
/brokers/ids/0. This probably indicates that you either have configured a
brokerid that is already in use, or else you have shutdown this broker and
restarted it faster than the zookeeper timeout so it appears to be
re-registering.
at
kafka.server.KafkaZooKeeper.registerBrokerInZk(KafkaZooKeeper.scala:57)
at
kafka.server.KafkaZooKeeper$SessionExpireListener.handleNewSession(KafkaZooKeeper.scala:100)
at org.I0Itec.zkclient.ZkClient$4.run(ZkClient.java:472)
at org.I0Itec.zkclient.ZkEventThread.run(ZkEventThread.java:71)
[2013-03-26 02:07:19,155] INFO re-registering broker info in ZK for broker
0 (kafka.server.KafkaZooKeeper)
[2013-03-26 02:07:19,155] INFO Registering broker /brokers/ids/0
(kafka.server.KafkaZooKeeper)
[2013-03-26 02:07:19,611] INFO conflict in /brokers/ids/0 data:
127.0.0.1-1364234839275:127.0.0.1:9093 stored data: 127.0.0.1-1364227372971:
127.0.0.1:9093 (kafka.utils.ZkUtils$)
[2013-03-26 02:07:19,611] ERROR Error handling event ZkEvent[New session
event sent to kafka.server.KafkaZooKeeper$SessionExpireListener@40f8c9bf]
(org.I0Itec.zkclient.ZkEventThread)
java.lang.RuntimeException: A broker is already registered on the path
/brokers/ids/0. This probably indicates that you either have configured a
brokerid that is already in use, or else you have shutdown this broker and
restarted it faster than the zookeeper timeout so it appears to be
re-registering.
at
kafka.server.KafkaZooKeeper.registerBrokerInZk(KafkaZooKeeper.scala:57)
at
kafka.server.KafkaZooKeeper$SessionExpireListener.handleNewSession(KafkaZooKeeper.scala:100)
at org.I0Itec.zkclient.ZkClient$4.run(ZkClient.java:472)
at org.I0Itec.zkclient.ZkEventThread.run(ZkEventThread.java:71)
2013/3/26 Neha Narkhede <neha.narkh...@gmail.com>
> That really depends on your consumer application's memory allocation
> patterns. If it is a thin wrapper over a Kafka consumer, I would imagine
> you can get away with using CMS for the tenured generation and parallel
> collector for the new generation with a small heap like 1gb or so.
>
> Thanks,
> Neha
>
> On Monday, March 25, 2013, Yonghui Zhao wrote:
>
> > Any suggestion on consumer side?
> > 在 2013-3-25 下午9:49，"Neha Narkhede" <neha.narkh...@gmail.com<javascript:;>
> > >写道：
> >
> > > For Kafka 0.7 in production at Linkedin, we use a heap of size 3G, new
> > gen
> > > 256 MB, CMS collector with occupancy of 70%.
> > >
> > > Thanks,
> > > Neha
> > >
> > > On Sunday, March 24, 2013, Yonghui Zhao wrote:
> > >
> > > > Hi Jun,
> > > >
> > > > I used kafka-server-start.sh to start kafka, there is only one jvm
> > > setting
> > > > "-Xmx512M“
> > > >
> > > > Do you have some recommend GC setting? Usually our sever has 32GB
> or
> > > 64GB
> > > > RAM.
> > > >
> > > > 2013/3/22 Jun Rao <jun...@gmail.com>
> > > >
> > > > > A typical reason for many rebalancing is the consumer side GC. If
> so,
> > > you
> > > > > will see logs in the consume saying sth like "expired session" for
> > ZK.
> > > > > Occasional rebalances are fine. Too many rebalances can slow down
> the
> > > > > consumption and you will need to tune your GC setting.
> > > > >
> > > > > Thanks,
> > > > >
> > > > > Jun
> > > > >
> > > > > On Thu, Mar 21, 2013 at 11:07 PM, Yonghui Zhao <
> > zhaoyong...@gmail.com
> > > > > >wrote:
> > > > >
> > > > > > Yes, before consumer exception:
> > > > > >
> > > > > > 2013/03/21 12:07:17.909 INFO [ZookeeperConsumerConnector] []
> > > > > > 0_lg-mc-db01.bj-1363784482043-f98c7868 *end rebalancing
> > > > > > consumer*0_lg-mc-db01.bj-1363784482043-f98c7868 try #0
> > > > > > 2013/03/21 12:07:17.911 INFO [ZookeeperConsumerConnector] []
> > > > > > 0_lg-mc-db01.bj-1363784482043-f98c7868 *begin rebalancing
> > > > > > consumer*0_lg-mc-db01.bj-1363784482043-f98c7868 try #0
> > > > > > 2013/03/21 12:07:17.934 INFO [FetcherRunnable] [] FetchRunnable-0
> > > start
> > > > > > fetching topic: sms part: 0 offset: 43667888259 from
> > 127.0.0.1:9093
> > > > > > 2013/03/21 12:07:17.940 INFO [SimpleConsumer] [] Reconnect in
> > > > multifetch
> > > > > > due to socket error:
> > > > > > java.nio.channels.*ClosedByInterruptException*
> > > > > > at java.nio.channels.spi.*AbstractInterruptibleChannel*
> > > > > > .end(AbstractInterruptibleChannel.java:201)
> > > > > >
> > > > > >
> > > > > > 2013/03/21 12:07:17.978 INFO [ZookeeperConsumerConnector] []
> > > > > > 0_lg-mc-db01.bj-1363784482043-f98c7868 *end rebalancing
> > > > > > consumer*0_lg-mc-db01.bj-1363784482043-f98c7868 try #0
> > > > > > 2013/03/21 12:07:18.004 INFO [FetcherRunnable] [] FetchRunnable-0
> > > start
> > > > > > fetching topic: sms part: 0 offset: 43667888259 from
> > 127.0.0.1:9093
> > > > > > 2013/03/21 12:07:18.066 INFO [ZookeeperConsumerConnector] []
> > > > > > 0_lg-mc-db01.bj-1363784482043-f98c7868 *begin rebalancing
> consume*r
> > > > > > 0_lg-mc-db01.bj-1363784482043-f98c7868 try #0
> > > > > > 2013/03/21 12:07:18.176 INFO [SimpleConsumer] [] Reconnect in
> > > > multifetch
> > > > > > due to socket error:
> > > > > > java.nio.channels.*ClosedByInterruptException*
> > > > > > at java.nio.channels.spi.*AbstractInterruptibleChannel*
> > > > > > .end(AbstractInterruptibleChannel.java:201)
> > > > > >
> > > > > >
> > > > > > So you think it is normal? How can we avoid this exception?
> > > > > >
> > > > > > I used 4 partitions in kafka, use only 1 partition？
> > > > > >
> > > > > >
> > > > > >
> > > > > > 2013/3/22 Jun Rao <jun...@gmail.com>
> > > > > >
> > > > > > > Do you see any rebalances in the consumer? Each rebalance will
> > > > > interrupt
> > > > > > > existing fetcher threads first.
> > > > > > >
> > > > > > > Thanks,
> > > > > > >
> > > > > > > Jun
> > > > > > >
> > > > > > > On Thu, Mar 21, 2013 at 9:40 PM, Yonghui Zhao <
> > > zhaoyong...@gmail.com
> >
>
