Reject series/write requests when max pending request limit is hit #114
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| level.Info(logger).Log("msg", "set max pending gRPC write request in limiter", "max_pending_requests", conf.maxPendingGrpcWriteRequests) | ||
| } | ||
| limiter, err := receive.NewLimiterWithOptions( | ||
| conf.writeLimitsConfig, |
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consider reuse the writeLimitsConfig so less interface changes?
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I agree that it'd be ideal to have this config field in writeLimitsConfig, but DB pods don't load writeLimitsConfig at all. Pantheon-writer pods load that config. I'll have to keep it this way.
The interface is not changed. receive.NewLimiter() stays the same. I added another function receive.NewLimiterWithOptions().
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got it, that's fair, do you wanna add some unit tests for limiter to test the load shedding behavior?
| // Value 0 disables the feature. | ||
| maxPendingRequests int32 | ||
| pendingRequests atomic.Int32 | ||
| maxPendingRequestLimitHit prometheus.Counter |
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LGTM. Shall we consider adding an alert around this metrics?
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Definitely once the counter is there.
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| @@ -1083,12 +1073,15 @@ func quorumReached(successes []int, successThreshold int) bool { | |||
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| // RemoteWrite implements the gRPC remote write handler for storepb.WriteableStore. | |||
| func (h *Handler) RemoteWrite(ctx context.Context, r *storepb.WriteRequest) (*storepb.WriteResponse, error) { | |||
| if h.Limiter.ShouldRejectNewRequest() { | |||
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nice, let's add a unit test for this behavior?
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I can do that in a follow-up PR while testing it in Dev. It's quite tricky to write a unit test for such a feature. I want to see how useful it's in Dev before spending time on it.
This is to prevent Receive server from begin overloaded
Tested in
dev-aws-eu-west-1