[jira] [Updated] (KAFKA-1670) Corrupt log files for segment.bytes values close to Int.MaxInt

["Sriharsha Chintalapani (JIRA)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/KAFKA-1670?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Sriharsha Chintalapani updated KAFKA-1670:
------------------------------------------
    Attachment: KAFKA-1670.patch

> Corrupt log files for segment.bytes values close to Int.MaxInt
> --------------------------------------------------------------
>
>                 Key: KAFKA-1670
>                 URL: https://issues.apache.org/jira/browse/KAFKA-1670
>             Project: Kafka
>          Issue Type: Bug
>    Affects Versions: 0.8.1.1
>            Reporter: Ryan Berdeen
>            Assignee: Sriharsha Chintalapani
>            Priority: Blocker
>         Attachments: KAFKA-1670.patch
>
>
> The maximum value for the topic-level config {{segment.bytes}} is {{Int.MaxInt}} (2147483647). *Using this value causes brokers to corrupt their log files, leaving them unreadable.*
> We set {{segment.bytes}} to {{2122317824}} which is well below the maximum. One by one, the ISR of all partitions shrunk to 1. Brokers would crash when restarted, attempting to read from a negative offset in a log file. After discovering that many segment files had grown to 4GB or more, we were forced to shut down our *entire production Kafka cluster* for several hours while we split all segment files into 1GB chunks.
> Looking into the {{kafka.log}} code, the {{segment.bytes}} parameter is used inconsistently. It is treated as a *soft* maximum for the size of the segment file (https://github.com/apache/kafka/blob/0.8.1.1/core/src/main/scala/kafka/log/LogConfig.scala#L26) with logs rolled only after (https://github.com/apache/kafka/blob/0.8.1.1/core/src/main/scala/kafka/log/Log.scala#L246) they exceed this value. However, much of the code that deals with log files uses *ints* to store the size of the file and the position in the file. Overflow of these ints leads the broker to append to the segments indefinitely, and to fail to read these segments for consuming or recovery.
> This is trivial to reproduce:
> {code}
> $ bin/kafka-topics.sh --topic segment-bytes-test --create --replication-factor 2 --partitions 1 --zookeeper zkhost:2181
> $ bin/kafka-topics.sh --topic segment-bytes-test --alter --config segment.bytes=2147483647 --zookeeper zkhost:2181
> $ yes "Int.MaxValue is a ridiculous bound on file size in 2014" | bin/kafka-console-producer.sh --broker-list localhost:6667 zkhost:2181 --topic segment-bytes-test
> {code}
> After running for a few minutes, the log file is corrupt:
> {code}
> $ ls -lh data/segment-bytes-test-0/
> total 9.7G
> -rw-r--r-- 1 root root  10M Oct  3 19:39 00000000000000000000.index
> -rw-r--r-- 1 root root 9.7G Oct  3 19:39 00000000000000000000.log
> {code}
> We recovered the data from the log files using a simple Python script: https://gist.github.com/also/9f823d9eb9dc0a410796



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