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Posted to dev@kafka.apache.org by "Ismael Juma (JIRA)" <ji...@apache.org> on 2016/07/05 09:27:11 UTC
[jira] [Issue Comment Deleted] (KAFKA-3047) Explicit offset
assignment in Log.append can corrupt the log
[ https://issues.apache.org/jira/browse/KAFKA-3047?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Ismael Juma updated KAFKA-3047:
-------------------------------
Comment: was deleted
(was: Good to know, thanks for explanation!)
> Explicit offset assignment in Log.append can corrupt the log
> ------------------------------------------------------------
>
> Key: KAFKA-3047
> URL: https://issues.apache.org/jira/browse/KAFKA-3047
> Project: Kafka
> Issue Type: Bug
> Components: log
> Affects Versions: 0.9.0.0
> Reporter: Maciek Makowski
> Assignee: Ismael Juma
> Fix For: 0.10.0.0
>
>
> {{Log.append()}} has {{assignOffsets}} parameter, which, when set to false, should cause Kafka to use the offsets specified in the {{ByteBufferMessageSet}} and not recalculate them based on {{nextOffsetMetadata}}. However, in that function, {{appendInfo.firstOffset}} is unconditionally set to {{nextOffsetMetadata.messageOffset}}. This can cause corruption of the log in the following scenario:
> * {{nextOffsetMetadata.messageOffset}} is 2001
> * {{append(messageSet, assignOffsets = false)}} is called, where {{messageSet}} contains offsets 1001...1500
> * after {{val appendInfo = analyzeAndValidateMessageSet(messages)}} call, {{appendInfo.fistOffset}} is 1001 and {{appendInfo.lastOffset}} is 1500
> * after {{appendInfo.firstOffset = nextOffsetMetadata.messageOffset}} call, {{appendInfo.fistOffset}} is 2001 and {{appendInfo.lastOffset}} is 1500
> * consistency check {{if(!appendInfo.offsetsMonotonic || appendInfo.firstOffset < nextOffsetMetadata.messageOffset)}} succeeds (the second condition can never fail due to unconditional assignment) and writing proceeds
> * the message set is appended to current log segment starting at offset 2001, but the offsets in the set are 1001...1500
> * the system shuts down abruptly
> * on restart, the following unrecoverable error is reported:
> {code}
> Exception in thread "main" kafka.common.InvalidOffsetException: Attempt to append an offset (1001) to position 12345 no larger than the last offset appended (1950) to xyz/00000000000000000000.index.
> at kafka.log.OffsetIndex$$anonfun$append$1.apply$mcV$sp(OffsetIndex.scala:207)
> at kafka.log.OffsetIndex$$anonfun$append$1.apply(OffsetIndex.scala:197)
> at kafka.log.OffsetIndex$$anonfun$append$1.apply(OffsetIndex.scala:197)
> at kafka.utils.CoreUtils$.inLock(CoreUtils.scala:262)
> at kafka.log.OffsetIndex.append(OffsetIndex.scala:197)
> at kafka.log.LogSegment.recover(LogSegment.scala:188)
> at kafka.log.Log$$anonfun$loadSegments$4.apply(Log.scala:188)
> at kafka.log.Log$$anonfun$loadSegments$4.apply(Log.scala:160)
> at scala.collection.TraversableLike$WithFilter$$anonfun$foreach$1.apply(TraversableLike.scala:778)
> at scala.collection.IndexedSeqOptimized$class.foreach(IndexedSeqOptimized.scala:33)
> at scala.collection.mutable.ArrayOps$ofRef.foreach(ArrayOps.scala:186)
> at scala.collection.TraversableLike$WithFilter.foreach(TraversableLike.scala:777)
> at kafka.log.Log.loadSegments(Log.scala:160)
> at kafka.log.Log.<init>(Log.scala:90)
> at kafka.log.LogManager$$anonfun$loadLogs$2$$anonfun$3$$anonfun$apply$10$$anonfun$apply$1.apply$mcV$sp(LogManager.scala:150)
> at kafka.utils.CoreUtils$$anon$1.run(CoreUtils.scala:60)
> at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
> at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
> at java.util.concurrent.FutureTask.run(FutureTask.java:166)
> at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
> at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
> at java.lang.Thread.run(Thread.java:722)
> {code}
> *Proposed fix:* the assignment {{appendInfo.firstOffset = nextOffsetMetadata.messageOffset}} should only happen in {{if (assignOffsets)}} branch of code.
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