> On Jan. 23, 2015, 4:47 p.m., Neha Narkhede wrote: > > core/src/main/scala/kafka/admin/ConsumerGroupCommand.scala, line 259 > > <https://reviews.apache.org/r/29831/diff/6/?file=829769#file829769line259> > > > > => If set along with --delete > > > > I'm not sure if I fully understood the purpose of force-delete. > > Basically, the only time safe for deleting a consumer group's offset > > information is if there are no live consumers in that group anymore. > > > > If so, --force-delete would mean deleting even if that is not true. > > This is pretty disruptive and I can't think of any case where this action > > will be useful. > > > > Thoughts? > > Onur Karaman wrote: > There are currently four types of delete: > bin/kafka-consumer-groups.sh --zookeeper 192.168.50.11:2181 --delete > --group g1 --group g5 > bin/kafka-consumer-groups.sh --zookeeper 192.168.50.11:2181 --delete > --group g3 --group g4 --topic t2 > bin/kafka-consumer-groups.sh --zookeeper 192.168.50.11:2181 --delete > --topic t1 > bin/kafka-consumer-groups.sh --zookeeper 192.168.50.11:2181 --delete > --topic t3 --force-delete > > --force-delete only applies to topic-wide delete. My concern was that > when you do a topic-wide delete, you can potentially impact many consumer > groups. So by default, topic-wide delete first checks if the topic still > exists. My reasoning was that if a topic still exists during a topic-wide > offset delete, it probably wasn't intentional. It overrides the default > behavior by ignoring the topic-existance check. > > One complication of the topic existance check is the following scenario: > 1. We delete topic t. > 2. t gets recreated due to some producers still producing events to t. > 3. We try to do a topic-wide offset delete on t. > 4. The check will prevent the offset delete from happening. > > --force-delete attempts to address that scenario. > > I agree that it is not safe to delete offsets while the group is active, > and none of the 4 deletes currently check for this. While it is documented, > it makes more sense to push this into the code.
Right, there are really 2 problems being discussed here - 1. Definition of a safe delete in any of the 4 options 2. Justification for providing the --force-delete option For 1., it is easier if we clearly state when any of these delete operations is safe, model that through the code. I think it is only when there are no active consumers in the group. For 2., I'm not sure that option is very useful and I'm wondering if we can do without it. Also, let's simplify topic-wide delete to also mean the same - consumer information will be deleted if there are no active consumers in the group. - Neha ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: https://reviews.apache.org/r/29831/#review69400 ----------------------------------------------------------- On Jan. 22, 2015, 10:32 a.m., Onur Karaman wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > https://reviews.apache.org/r/29831/ > ----------------------------------------------------------- > > (Updated Jan. 22, 2015, 10:32 a.m.) > > > Review request for kafka. > > > Bugs: KAFKA-1476 > https://issues.apache.org/jira/browse/KAFKA-1476 > > > Repository: kafka > > > Description > ------- > > Merged in work for KAFKA-1476 and sub-task KAFKA-1826 > > > Diffs > ----- > > bin/kafka-consumer-groups.sh PRE-CREATION > core/src/main/scala/kafka/admin/AdminUtils.scala > 28b12c7b89a56c113b665fbde1b95f873f8624a3 > core/src/main/scala/kafka/admin/ConsumerGroupCommand.scala PRE-CREATION > core/src/main/scala/kafka/utils/ZkUtils.scala > c14bd455b6642f5e6eb254670bef9f57ae41d6cb > core/src/test/scala/unit/kafka/admin/DeleteConsumerGroupTest.scala > PRE-CREATION > core/src/test/scala/unit/kafka/utils/TestUtils.scala > ac15d34425795d5be20c51b01fa1108bdcd66583 > > Diff: https://reviews.apache.org/r/29831/diff/ > > > Testing > ------- > > > Thanks, > > Onur Karaman > >
