[ROCKETMQ-192] Move consumer group rebalance from client to server ??

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Feedback Received
• Affects Version/s: 4.2.0
• Fix Version/s: 4.2.0
• Component/s: rocketmq-client
• Assignee: Xiaorui Wang
• Reporter: zhaoziyan
• Created: 04/May/17 07:13
• Updated: 13/Dec/17 12:18
• Resolved: 13/Dec/17 12:18

Description

Consumer Started.
Consumer Started.
Consumer Started.
Consumer Started.
RunHello [i=0, num=281]

{/192.168.185.172:10911@2=31, /192.168.185.172:10911@0=125, /192.168.185.172:10911@1=125}

RunHello [i=1, num=250]

{/192.168.185.172:10911@2=125, /192.168.185.172:10911@3=125}

RunHello [i=2, num=250]

{/192.168.186.131:10911@1=125, /192.168.186.131:10911@0=125}

RunHello [i=3, num=250]

{/192.168.186.131:10911@3=125, /192.168.186.131:10911@2=125}

SIZE=1000
重复31

Here is my test，I send 1000 msg to the topic.
The Test show the client may consume the same queue in some case. because of the current Group rebalance is doing by the consumer side,in some case , the consumer may have diffent view of All Consumer ids.
for Example: the consumer id 1 see have 3 consumers,but the consumer id 2 only see 2 consumers, so the same queue may hold by two consumer.

Kakfa 0.8.2 to 0.9 have redesign the client, move the Group rebalance to server side, have we need also move the Rebalance to server side ??