Hello,
I'm investigating an issue in which a Kafka Streams application does not
consume from one of the partitions it was assigned. I'm using the 2.3.0
version.
All the fetch requests are sent for two partitions only:
> Using older server API v6 to send FETCH
{replica_id=-1,max_wait_time=500,min_bytes=1,max_bytes=52428800,isolation_level=0,topics=[{topic=Topic_v2,partitions=[{partition=25,fetch_offset=71484113,log_start_offset=-1,partition_max_bytes=1048576},{partition=22,fetch_offset=71296374,log_start_offset=-1,partition_max_bytes=1048576}]}]}
with correlation id 1049090 to node 1
But there should be three of them; using kafka-consumer-groups.sh I can
see that the third one (partition 23) that has no current offset.
> Topic_v2 22 71296374 71296374 0
Topic-c1f03-StreamThread-1-consumer
> Topic_v2 23 - 72830772 -
Topic-c1f03-StreamThread-1-consumer
> Topic_v2 25 71484113 71484113 0
Topic-c1f03-StreamThread-1-consumer
It worked fine until the partition was revoked, but absolutely nothing
happened afterwards. Notice that the (shortened by me) clientId has
changed.
> 2019-07-10 02:15:36.347 [INFO]
ConsumerCoordinator:Topic-c1f03-StreamThread-1 - [Consumer
clientId=Topic-c1f03-StreamThread-1-consumer, groupId=Topic] Setting
offset for partition Topic_v2-23 to the committed offset
FetchPosition{offset=68735327, offsetEpoch=Optional.empty,
currentLeader=LeaderAndEpoch{leader=ip-10-0-1-81.us-west-2.compute.internal:9092
(id: 3 rack: null), epoch=-1}}
> 2019-07-10 02:15:36.383 [INFO]
ConsumerCoordinator:Topic-3e717-StreamThread-1 - [Consumer
clientId=Topic-3e717-StreamThread-1-consumer, groupId=Topic] Revoking
previously assigned partitions [Topic_v2-23]
> 2019-07-10 02:15:36.498 [INFO]
ConsumerCoordinator:Topic-3e717-StreamThread-1 - [Consumer
clientId=Topic-3e717-StreamThread-1-consumer, groupId=Topic] Setting
newly assigned partitions: Topic_v2-23
> 2019-07-10 02:15:36.506 [INFO]
ConsumerCoordinator:Topic-3e717-StreamThread-1 - [Consumer
clientId=Topic-3e717-StreamThread-1-consumer, groupId=Topic] Setting
offset for partition Topic_v2-23 to the committed offset
FetchPosition{offset=70030508, offsetEpoch=Optional.empty,
currentLeader=LeaderAndEpoch{leader=ip-10-0-1-81.us-west-2.compute.internal:9092
(id: 3 rack: null), epoch=-1}}
What could be a reason that this partition is not included in the fetch
request? It uses a single thread to process it (num.stream.threads set
to 1), so if the thread was locked it couldn't keep working on two other
partitions, if I understand correctly.
