One more +1
Thanks for the +1's I've went ahead and created a JIRA issue https://issues.apache.org/jira/browse/STORM-399 and pull request https://github.com/apache/incubator-storm/pull/183
Danijel and P. Taylor please +1 in JIRAThanks again!On Wed, Jul 9, 2014 at 2:48 PM, P. Taylor Goetz <email@example.com> wrote:
I'm +1 as well.
On Jul 9, 2014, at 4:03 PM, Danijel Schiavuzzi <firstname.lastname@example.org> wrote:
I'm also +1 on this.The old spout behaviour was perfectly fine. I guess maxOffsetBehind was added as a protection against fetching unavailable Kafka offsets, but it doesn't really make sense to me, in my Trident transactional topology where I can't afford to lose any data. I would rather have my spout stop processing data in this case, than skipping some offsets because of an arbitrary maxOffsetBehind config value. Others opinions may vary, but I think
setting this to Long.MAX_VALUE would make a much better default, as it would be closer to the old spout behaviour.
On Wednesday, July 9, 2014, Curtis Allen <email@example.com> wrote:
I’ve recently upgraded to storm and storm-kafka
0.9.2-incubating, replacing the https://github.com/wurstmeister/storm-kafka-0.8-plus spout I was using previously.
I have a large kafka log that I needed processed. I started my topology with
storm.kafka.SpoutConfig spoutConfig = new SpoutConfig.... spoutConfig.forceFromStart = true;
I then needed to make some tweaks in my application code and restarted the topology with
spoutConfig.forceFromStart = false. Expecting to pick up where I left off in my kafka log. Instead the kafka spout started from the latest offset. Upon investigation I found this log message in my storm worker logs
2014-07-09 18:02:15 s.k.PartitionManager [INFO] Read last commit offset from zookeeper: 15266940; old topology_id: ef3f1f89-f64c-4947-b6eb-0c7fb9adb9ea - new topology_id: 5747dba6-c947-4c4f-af4a-4f50a84817bf 2014-07-09 18:02:15 s.k.PartitionManager [INFO] Last commit offset from zookeeper: 15266940 2014-07-09 18:02:15 s.k.PartitionManager [INFO] Commit offset 22092614 is more than 100000 behind, resetting to startOffsetTime=-2 2014-07-09 18:02:15 s.k.PartitionManager [INFO] Starting Kafka prd-use1c-pr-08-kafka-kamq-0004:4 from offset 22092614
Digging in the storm-kafka spout I found this line
To fix this problem I ended up setting my spout config like so
spoutConf.maxOffsetBehind = Long.MAX_VALUE;
Now finally to my question.
Why would the kafka spout skip to the latest offset if the current offset is more then 100000 behind by default?
This seems like a bad default value, the spout literally skipped over months of data without any warning.
Are the core contributors open to accepting a pull request that would set the default to