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ASF GitHub Bot commented on KAFKA-3559: --------------------------------------- Github user enothereska closed the pull request at: https://github.com/apache/kafka/pull/2032 > Task creation time taking too long in rebalance callback > -------------------------------------------------------- > > Key: KAFKA-3559 > URL: https://issues.apache.org/jira/browse/KAFKA-3559 > Project: Kafka > Issue Type: Improvement > Components: streams > Reporter: Guozhang Wang > Assignee: Eno Thereska > Labels: architecture > Fix For: 0.10.2.0 > > > Currently in Kafka Streams, we create stream tasks upon getting newly > assigned partitions in rebalance callback function {code} onPartitionAssigned > {code}, which involves initialization of the processor state stores as well > (including opening the rocksDB, restore the store from changelog, etc, which > takes time). > With a large number of state stores, the initialization time itself could > take tens of seconds, which usually is larger than the consumer session > timeout. As a result, when the callback is completed, the consumer is already > treated as failed by the coordinator and rebalance again. > We need to consider if we can optimize the initialization process, or move it > out of the callback function, and while initializing the stores one-by-one, > use poll call to send heartbeats to avoid being kicked out by coordinator. -- This message was sent by Atlassian JIRA (v6.3.4#6332)