kafka server is started by bin/kafka-server-start.sh. No gc setting. 在 2013-3-26 下午11:40，"Neha Narkhede" <neha.narkh...@gmail.com>写道：
> Did you have a gc pause around that time on the server ? What are your > server's current gc settings ? > > Thanks, > Neha > > On Mon, Mar 25, 2013 at 8:48 PM, Yonghui Zhao <zhaoyong...@gmail.com> > wrote: > > 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 > >> > > >> >
