Report lag stats in poller #7490
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Signed-off-by: crowu <y.wu4515@gmail.com>
5antelope
requested review from
harshit-gangal,
shlomi-noach and
systay
as code owners
5antelope
requested review from
rohit-nayak-ps and
deepthi
and removed request for
systay,
shlomi-noach and
harshit-gangal
| "vitess.io/vitess/go/vt/mysqlctl" | ||
| vtrpcpb "vitess.io/vitess/go/vt/proto/vtrpc" | ||
| "vitess.io/vitess/go/vt/vterrors" | ||
| ) | ||
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| var replicationLagGauges = stats.NewGaugesWithMultiLabels( |
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None of the vttablet metrics have the keyspace/shard dimensions because by definition a tablet belongs to only one keyspace/shard. This can be a simple gauge (NewGauge).
Also the name should include the units - replicationLagMs or replicationLagNs.
HeartbeatLag is being reported in nanoseconds so we should probably do the same here.
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Sure, I renamed the gauge to replicationLagSec since we always assume the lag in seconds (e.g., we have SecondsBehindMaster and also cast the duration to sec on line 60)
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That makes more sense than ns :)
Signed-off-by: crowu <y.wu4515@gmail.com>
| "vitess.io/vitess/go/vt/mysqlctl" | ||
| vtrpcpb "vitess.io/vitess/go/vt/proto/vtrpc" | ||
| "vitess.io/vitess/go/vt/vterrors" | ||
| ) | ||
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| var replicationLagGauges = stats.NewGauge("replicationLagSec", "replication lag in seconds") |
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Sorry to be nitpicky, but could you rename the variable? It can be the same: replicationLagSec or even rename both the variable and gauge to replicationLagSeconds.
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Yep, good catch. I was going to do that initially as well :-)
Signed-off-by: crowu y.wu4515@gmail.com
Description
I think if polling is the default recommendation given how VTGate gateway works. This PR reports lag stats from poller so that we can track which replica is "unhealthy"
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Checklist
Deployment Notes
Impacted Areas in Vitess
Components that this PR will affect: