Page History

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To reduce # of open sockets, in 0.8.0 (https://issues.apache.org/jira/browse/KAFKA-1017), when the partitioning key is not specified or null, a producer will pick a random partition and stick to it for some time (default is 10 mins) before switching to another one. So, if there are fewer producers than partitions, at a given point of time, some partitions may not receive any data. To alleviate this problem, one can either reduce the metadata refresh interval or specify a message key and a customized random partitioner. For more detail see this thread http://mail-archives.apache.org/mod_mbox/kafka-dev/201310.mbox/%3CCAFbh0Q0aVh%2Bvqxfy7H-%2BMnRFBt6BnyoZk1LWBoMspwSmTqUKMg%40mail.gmail.com%3E

Consumers

Why does my consumer never get any data?

By default, when a consumer is started for the very first time, it ignores all existing data in a topic and will only consume new data coming in after the consumer is started. If this is the case, try sending some more data after the consumer is started. Alternatively, you can configure the consumer by setting auto.offset.reset to "smallest".

Why does my consumer get InvalidMessageSizeException?

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