Refactor: Engine::initialize() sets server state to Candidate #296
Conversation
- Feature: impl TryFrom<BTreeMap> for Membership. - part of databendlabs#292
| self.commands.push(Command::MoveInputCursorBy { n: l }); | ||
|
|
||
| // With the new config, start to elect to become leader |
There was a problem hiding this comment.
I can not get the point: why the node init state is candidate instead of follower?
There was a problem hiding this comment.
it means no matter the node startup in whatever situation, even if it join a cluster, it must start an election?
There was a problem hiding this comment.
After initializing the cluster(by appending a membership log), the cluster should elect a leader ASAP.
The behavior for a follower is to wait for a timeout before starting elect(by entering candidate state). Thus we can just avoid the follower state and enter candidate state at once.
There was a problem hiding this comment.
it means no matter the node startup in whatever situation, even if it join a cluster, it must start an election?
It must be a mistake to join a node into an existing cluster by initialize() it.
To join, it does not call initialize().
It should send a change-membership RPC to the existing cluster leader to start replicating logs to the new node.
There was a problem hiding this comment.
it means no matter the node startup in whatever situation, even if it join a cluster, it must start an election?
BTW, the election will never win. The new node does not have any log on it thus it will be rejected.
There was a problem hiding this comment.
seems to me that init as a follower or a candidate has not too much different, they all have advantages and disadvantages, as you like:)
Changelog
Refactor: Engine::initialize() sets server state to Candidate
Feature: impl TryFrom for Membership.
part of Impl
initialize()for engine #292This change is