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Large UDP payloads can be silently dropped

Open malish8632 opened this issue 5 years ago • 4 comments

Due to nature of UDP protocol data could be silently dropped if reached specific limits. As the data/metrics are dropped silently usually we alerted by teams noticing missing metrics.

One idea discussed is to put some ignorable/optional metric indicating the number of bytes or metrics sent over the wire so FFWD agent could detect the loss and emit a metric to be alerted on.

malish8632 avatar Jul 10 '20 16:07 malish8632

Good suggestion. Or a checksum if we want to be really stingy with bandwidth.

sming avatar Jul 10 '20 16:07 sming

@malish8632 do we know that limit ?

ao2017 avatar Sep 09 '20 12:09 ao2017

Yes the default is ~25MB. Check troubleshooting section in protobuf docs here.

malish8632 avatar Sep 09 '20 12:09 malish8632

Well, I wanted more datapoint from teams that are experiencing the problem.I doubt anybody is sending 25MB in the packet. I think the packets drop before reaching UDP max. I noticed, but I am not certain, that anything higher than 2048 bytes is being dropped. I will look into the issue when I get a chance.

ao2017 avatar Sep 14 '20 15:09 ao2017