Hi, It is likely due to the timestamps you are extracting and using as the record timestamp. Kafka uses the record timestamps for retention. I suspect this is causing your segments to roll and be deleted.
Thanks, Damian On Fri, 15 Dec 2017 at 11:49 Wim Van Leuven <wim.vanleu...@highestpoint.biz> wrote: > Hello all, > > We are running some Kafka Streams processing apps over Confluent OS > (v3.2.0) and I'm seeing unexpected but 'consitent' behaviour regarding > segment and index deletion. > > So, we have a topic 'input' that contains about 30M records to ingest. A > 1st processor transforms and pipes the data onto a second, intermediate > topic. A 2nd processor picks up the records, treats them and sends them > out. > > On our test environment the intermediate topic was set up with a retention > of 1 hour because we don't need to keep the data, only while processing. > > On a test run we saw the 2nd processor exit with exceptions that it > couldn't read offsets. We do not automatically reset because it should not > happen. > > org.apache.kafka.streams.errors.StreamsException: No valid committed offset > found for input topic cdr-raw-arch (partition 1) and no valid reset policy > configured. You need to set configuration parameter "auto.offset.reset" or > specify a topic specific reset policy via > KStreamBuilder#stream(StreamsConfig.AutoOffsetReset offsetReset, ...) or > KStreamBuilder#table(StreamsConfig.AutoOffsetReset offsetReset, ...) > > As we thought that it's the topic data expiring (processing takes longer > than 1 hour) we changed the topic to retain the data for 1 day. > > On rerun, we however saw exactly the same behaviour. That's why I'm saying > 'consistent behaviour' above. > > In the server logs, we see that kafka is rolling segments but immediately > scheduling them for deletion. > > [2017-12-15 11:01:46,992] INFO Rolled new log segment for > 'cdr-raw-arch-1' in 1 ms. (kafka.log.Log) > [2017-12-15 11:01:46,993] INFO Scheduling log segment 7330185 for log > cdr-raw-arch-1 for deletion. (kafka.log.Log) > [2017-12-15 11:01:46,995] INFO Rolled new log segment for > 'cdr-raw-arch-0' in 2 ms. (kafka.log.Log) > [2017-12-15 11:01:46,995] INFO Scheduling log segment 7335872 for log > cdr-raw-arch-0 for deletion. (kafka.log.Log) > [2017-12-15 11:02:46,995] INFO Deleting segment 7330185 from log > cdr-raw-arch-1. (kafka.log.Log) > [2017-12-15 11:02:46,996] INFO Deleting segment 7335872 from log > cdr-raw-arch-0. (kafka.log.Log) > [2017-12-15 11:02:47,170] INFO Deleting index > /data/4/kafka/cdr-raw-arch-1/00000000000007330185.index.deleted > (kafka.log.OffsetIndex) > [2017-12-15 11:02:47,171] INFO Deleting index > /data/4/kafka/cdr-raw-arch-1/00000000000007330185.timeindex.deleted > (kafka.log.TimeIndex) > [2017-12-15 11:02:47,172] INFO Deleting index > /data/3/kafka/cdr-raw-arch-0/00000000000007335872.index.deleted > (kafka.log.OffsetIndex) > [2017-12-15 11:02:47,173] INFO Deleting index > /data/3/kafka/cdr-raw-arch-0/00000000000007335872.timeindex.deleted > (kafka.log.TimeIndex) > > > However, I do not understand the behaviour: Why is kafka deleting the data > on the intermediary topic before it got processed? Almost immediately even? > > We do use timestamp extractors to pull business time from the records. Is > that taken into account for retention time? Or is retention only based on > times of the files on disk? > > Thank you to shed any light on this problem! > > Kind regards! > -wim >
