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https://issues.apache.org/jira/browse/KAFKA-2303?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14643136#comment-14643136
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Alexander Demidko commented on KAFKA-2303:
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I think in our case we had too many unique keys per partition, so making
compactions to happen more frequently will not ultimately solve the issue.
Increasing partitions number should help, but it requires more careful planning
about the compacted topic overall data volumes.
> Fix for KAFKA-2235 LogCleaner offset map overflow causes another compaction
> failures
> ------------------------------------------------------------------------------------
>
> Key: KAFKA-2303
> URL: https://issues.apache.org/jira/browse/KAFKA-2303
> Project: Kafka
> Issue Type: Bug
> Components: core, log
> Affects Versions: 0.8.2.1
> Reporter: Alexander Demidko
> Assignee: Jay Kreps
> Fix For: 0.8.3
>
>
> We have rolled out the patch for KAFKA-2235 to our kafka cluster, and
> recently instead of
> {code}
> "kafka.log.LogCleaner - [kafka-log-cleaner-thread-0], Error due to
> java.lang.IllegalArgumentException: requirement failed: Attempt to add a new
> entry to a full offset map."
> {code}
> we started to see
> {code}
> kafka.log.LogCleaner - [kafka-log-cleaner-thread-0], Error due to
> java.lang.IllegalArgumentException: requirement failed: 131390902 messages in
> segment <topic-name>-cgstate-8/00000000000079840768.log but offset map can
> fit only 80530612. You can increase log.cleaner.dedupe.buffer.size or
> decrease log.cleaner.threads
> {code}
> So, we had to roll it back to avoid disk depletion although I'm not sure if
> it needs to be rolled back in trunk. This patch applies more strict checks
> than were in place before: even if there is only one unique key for a
> segment, cleanup will fail if this segment is too big.
> Does it make sense to eliminate a limit for the offset map slots count, for
> example to use an offset map backed by a memory mapped file?
> The limit of 80530612 slots comes from memory / bytesPerEntry, where memory
> is Int.MaxValue (we use only one cleaner thread) and bytesPerEntry is 8 +
> digest hash size. Might be wrong, but it seems if the overall number of
> unique keys per partition is more than 80M slots in an OffsetMap, compaction
> will always fail and cleaner thread will die.
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