Hi Yaolong, Concurrent mode seems great, I’ve created a Jira at https://issues.apache.org/jira/browse/RATIS-1592 <https://issues.apache.org/jira/browse/RATIS-1592>
Best Wishes William Song > 2022年6月14日 12:56，yaolongliu <[email protected]> 写道： > > Hi William: > > I have an idea whether it is possible to add a mode to setConfiguration, > called concurrent mode, in this mode: we only add members to the new member > list that are temporarily not in the current list, and do not delete existing > members. Consider the following scenarios: > Suppose there are now three members A B C in the cluster, > > D called setConfiguration(newPeers=[A, B, C, D]) > E called setConfiguration(newPeers=[A, B, C, E]) > In the current code logic, the cluster members will end up being A, B, C, D > or A, B, C, E, but what we want is A, B, C, D, E > > In concurrent mode: > We assume that E's request is executed successfully first, and the current > members of the cluster are A, B, C, E, and then start to execute D's request. > At this time, we find that D is not in the list, so we just add D instead of > deleting E. The clusters eventually become A, B, C, D, E > In addition, we can hand over to the user whether to use concurrent mode to > execute setConfiguration. Also, could you create a jira to discuss this, > thanks! > > Best Wishes, > Yaolong Liu > >> 2022年6月14日 上午10:57，William Song <[email protected]> 写道： >> >> Hi all, >> >> We met problems on concurrent setConfiguration scenario and we want to seek >> for your help. >> >> Consider the scenario where group contains A as leader, and B/C both want to >> join the group. Since B and C are not aware of each other during start up, >> they send request as follows: >> 1. B called setConfiguration(newPeers=[A,B]) >> 2. C called setConfiguration(newPeers=[A,C]) >> The two requests arrive A concurrently, both successfully executed, which >> lead to only B or C can participate in the final configuration, not B and C >> as expected. >> >> How are we supposed to handle this scenario? >> >> Best wishes, >> William Song >> >>
