What config property values did you use on producer/consumer/broker? Guozhang
On Tue, Jul 15, 2014 at 10:32 AM, Jiang Wu (Pricehistory) (BLOOMBERG/ 731 LEX -) <jwu...@bloomberg.net> wrote: > Guozhang, > I'm testing on 0.8.1.1; just kill pid, no -9. > Regards, > Jiang > > From: users@kafka.apache.org At: Jul 15 2014 13:27:50 > To: JIANG WU (PRICEHISTORY) (BLOOMBERG/ 731 LEX -), users@kafka.apache.org > Subject: Re: message loss for sync producer, acks=2, topic replicas=3 > > Hello Jiang, > > Which version of Kafka are you using, and did you kill the broker with -9? > > Guozhang > > > On Tue, Jul 15, 2014 at 9:23 AM, Jiang Wu (Pricehistory) (BLOOMBERG/ 731 > LEX -) <jwu...@bloomberg.net> wrote: > > > Hi, > > I observed some unexpected message loss in kafka fault tolerant test. In > > the test, a topic with 3 replicas is created. A sync producer with acks=2 > > publishes to the topic. A consumer consumes from the topic and tracks > > message ids. During the test, the leader is killed. Both producer and > > consumer continue to run for a while. After the producer stops, the > > consumer reports if all messages are received. > > > > The test was repeated multiple rounds; message loss happened in about 10% > > of the tests. A typical scenario is as follows: before the leader is > > killed, all 3 replicas are in ISR. After the leader is killed, one > follower > > becomes the leader, and 2 replicas (including the new leader) are in ISR. > > Both the producer and consumer pause for several seconds during that > time, > > and then continue. Message loss happens after the leader is killed. > > > > Because the new leader is in ISR before the old leader is killed, unclean > > leader election doesn't explain the message loss. > > > > I'm wondering if anyone else also observed such message loss? Is there > any > > known issue that may cause the message loss in the above scenario? > > > > Thanks, > > Jiang > > > -- > -- Guozhang > > > -- -- Guozhang