Github user hmcl commented on a diff in the pull request:
https://github.com/apache/storm/pull/1605#discussion_r79570505
--- Diff:
external/storm-kafka-client/src/main/java/org/apache/storm/kafka/spout/KafkaSpoutRetryExponentialBackoff.java
---
@@ -144,7 +145,12 @@ public String toString() {
/**
* The time stamp of the next retry is scheduled according to the
exponential backoff formula ( geometric progression):
* nextRetry = failCount == 1 ? currentTime + initialDelay :
currentTime + delayPeriod^(failCount-1) where failCount = 1, 2, 3, ...
- * nextRetry = Min(nextRetry, currentTime + maxDelay)
+ * nextRetry = Min(nextRetry, currentTime + maxDelay).
+ *
+ * While retrying a record, no new records are committed until the
previous polled records have been acked. This guarantees at once delivery of
--- End diff --
This comment should probably not go here, but rather somewhere in the Spout
code. (retry service knows nothing about exactly once or at most once semantics)
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---
