docs: Describe congestion fundamentals #10873
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| But this is not ideal Just consider this example where everybody tries to access | ||
| a contract on the same shard. | ||
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Depending on how it's interpreted the graph may also need a 999 Tgas arrow from shard 3 to itself and then the arrow to sink should be 2997 Tgas.
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I agree for the arrow shard3 -> shard3. But I think it should still be 2998 Tgas. Otherwise the sum of flows from the source is not equal to the sum to the sinks. It would be 2997 Tgas for the receipts and 1 Tgas for conversion, both should point to sink, showing that the gas has been burnt.
I'm adding the arrows to the two graphs as best as I can without it getting too unreadable... Aligning things isn't always easy in graphviz graphs^^
| The sad thing is, there is no way around it in the most general case. A | ||
| congestion control strategy that does apply this limit to this workload will | ||
| always have infinitely sized queues. |
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It's the other way around, a strategy that accepts more than this limit will have unbounded queues.
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Right^^ I think a "not" went missing somewhere, I'll add one to correct it.
This document describes a few fundamental congestion control problems and ideas to solve them.
The added page serves as secondary document to NEP to summarise the thought process behind the most important design decisions. But it is generally applicable to congestion in Near Protocol's receipt execution system as it works today. It can even serve as documentation for how congestion can occur today.
The document includes 8 graphs generated using graphviz.
To regenerate after modifying the
*.dotfiles, install the graphviz toolbox (on systems with apt:sudo apt install graphviz) and then rundot -Tsvg img_name.dot > img_name.svg.