Justin Miller commented on SPARK-17147:

K I'll try to assemble everything I've seen so far around it and post it to the 
list. Thanks!

> Spark Streaming Kafka 0.10 Consumer Can't Handle Non-consecutive Offsets 
> (i.e. Log Compaction)
> ----------------------------------------------------------------------------------------------
>                 Key: SPARK-17147
>                 URL: https://issues.apache.org/jira/browse/SPARK-17147
>             Project: Spark
>          Issue Type: Bug
>          Components: Streaming
>    Affects Versions: 2.0.0
>            Reporter: Robert Conrad
> When Kafka does log compaction offsets often end up with gaps, meaning the 
> next requested offset will be frequently not be offset+1. The logic in 
> KafkaRDD & CachedKafkaConsumer has a baked in assumption that the next offset 
> will always be just an increment of 1 above the previous offset. 
> I have worked around this problem by changing CachedKafkaConsumer to use the 
> returned record's offset, from:
> {{nextOffset = offset + 1}}
> to:
> {{nextOffset = record.offset + 1}}
> and changed KafkaRDD from:
> {{requestOffset += 1}}
> to:
> {{requestOffset = r.offset() + 1}}
> (I also had to change some assert logic in CachedKafkaConsumer).
> There's a strong possibility that I have misconstrued how to use the 
> streaming kafka consumer, and I'm happy to close this out if that's the case. 
> If, however, it is supposed to support non-consecutive offsets (e.g. due to 
> log compaction) I am also happy to contribute a PR.

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