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Guozhang Wang commented on KAFKA-1011: -------------------------------------- Besides batching, two other critical functions that was missing from SyncProducer are partition-leader-discovery and retry-on-failure. I think without those the MirrorMaker SyncProducer will not work. > Decompression and re-compression on MirrorMaker could result in messages > being dropped in the pipeline > ------------------------------------------------------------------------------------------------------ > > Key: KAFKA-1011 > URL: https://issues.apache.org/jira/browse/KAFKA-1011 > Project: Kafka > Issue Type: Bug > Reporter: Guozhang Wang > Assignee: Guozhang Wang > Fix For: 0.8.1 > > Attachments: KAFKA-1011.v1.patch > > > The way MirrorMaker works today is that its consumers could use deep iterator > to decompress messages received from the source brokers and its producers > could re-compress the messages while sending them to the target brokers. > Since MirrorMakers use a centralized data channel for its consumers to pipe > messages to its producers, and since producers would compress messages with > the same topic within a batch as a single produce request, this could result > in messages accepted at the front end of the pipeline being dropped at the > target brokers of the MirrorMaker due to MesageSizeTooLargeException if it > happens that one batch of messages contain too many messages of the same > topic in MirrorMaker's producer. If we can use shallow iterator at the > MirrorMaker's consumer side to directly pipe compressed messages this issue > can be fixed. > Also as Swapnil pointed out, currently if the MirrorMaker lags and there are > large messages in the MirrorMaker queue (large after decompression), it can > run into an OutOfMemoryException. Shallow iteration will be very helpful in > avoiding this exception. > The proposed solution of this issue is also related to KAFKA-527. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira