(Jin Qing's Column, Dec., 2021)
Try to find out why Orleans need a DeathVoteExpirationTimeout config.
https://dotnet.github.io/orleans/docs/implementation/cluster_management.html#extension-to-totally-order-membership-views
DeathVoteExpirationTimeout - Expiration time in seconds for death vote in the membership table. Default is 120 seconds
GetFreshVotes
DeathVoteExpirationTimeout is only used by GetFreshVotes(), which has 3 occurence:
class ClusterHealthMonitor { ... private UpdateMonitoredSilos(...) { ... bool isSuspected = candidateEntry.GetFreshVotes(now, DeathVoteExpirationTimeout).Count > 0; ... } }
class LocalSiloHealthMonitor { ... private int CheckSuspectingNodes(DateTime now, List<string> complaints) { ... var freshVotes = membershipEntry.GetFreshVotes(now, DeathVoteExpirationTimeout); ... } ... }
class MembershipTableManager { ... public TryToSuspectOrKill(SiloAddress silo) { ... // get all valid (non-expired) votes var freshVotes = entry.GetFreshVotes(DateTime.UtcNow, DeathVoteExpirationTimeout); ... } ... }
GetFreshVotes() uses this expiration time to ignore old voter:
internal GetFreshVotes(DateTime now, TimeSpan expiration) { ... foreach (var voter in this.SuspectTimes) { var otherVoterTime = voter.Item2; if (now.Subtract(otherVoterTime) < expiration) { result.Add(voter); } } return result.ToImmutable(); }
Powered by: C++博客 Copyright © 金慶