Fix the election was reset wrongly before failover epoch was obtained #1339
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After valkey-io#1009, we will reset the election when we received a claim with an equal or higher epoch since a node can win an election in the past. But we need to consider the time before the node actually obtains the failover_auth_epoch. The failover_auth_epoch default is 0, so before the node actually get the failover epoch, we might wrongly reset the election. This is probably harmless, but will produce misleading log output and may delay election by a cron cycle or beforesleep. Now we will only reset the election when a node is actually obtains the failover epoch. Signed-off-by: Binbin <binloveplay1314@qq.com>
Codecov ReportAll modified and coverable lines are covered by tests ✅
Additional details and impacted files@@ Coverage Diff @@
## unstable #1339 +/- ##
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- Coverage 70.76% 70.61% -0.16%
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Files 116 116
Lines 63271 63281 +10
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- Hits 44776 44688 -88
- Misses 18495 18593 +98
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zuiderkwast
approved these changes
Nov 28, 2024
Comment on lines
-3150
to
3154
| if (server.cluster->failover_auth_time && sender->configEpoch >= server.cluster->failover_auth_epoch) { | ||
| if (server.cluster->failover_auth_time && server.cluster->failover_auth_sent && | ||
| sender->configEpoch >= server.cluster->failover_auth_epoch) { | ||
| /* Another node has claimed an epoch greater than or equal to ours. | ||
| * If we have an ongoing election, reset it because we cannot win | ||
| * with an epoch smaller than or equal to the incoming claim. This |
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Yes, this comment even says "If we have an ongoing election, reset it", so it's good to check that we actually have an ongoing election (failover_auth_sent). Very clear.
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After #1009, we will reset the election when we received
a claim with an equal or higher epoch since a node can win
an election in the past.
But we need to consider the time before the node actually
obtains the failover_auth_epoch. The failover_auth_epoch
default is 0, so before the node actually get the failover
epoch, we might wrongly reset the election.
This is probably harmless, but will produce misleading log
output and may delay election by a cron cycle or beforesleep.
Now we will only reset the election when a node is actually
obtains the failover epoch.