37 lines
1.5 KiB
Markdown
37 lines
1.5 KiB
Markdown
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# Concepts
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## Gas & Fees
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Fees serve two purposes for an operator of the network.
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Fees limit the growth of the state stored by every full node and allow for
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general purpose censorship of transactions of little economic value. Fees
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are best suited as an anti-spam mechanism where validators are disinterested in
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the use of the network and identities of users.
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Fees are determined by the gas limits and gas prices transactions provide, where
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`fees = ceil(gasLimit * gasPrices)`. Txs incur gas costs for all state reads/writes,
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signature verification, as well as costs proportional to the tx size. Operators
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should set minimum gas prices when starting their nodes. They must set the unit
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costs of gas in each token denomination they wish to support:
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`simd start ... --minimum-gas-prices=0.00001stake;0.05photinos`
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When adding transactions to mempool or gossipping transactions, validators check
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if the transaction's gas prices, which are determined by the provided fees, meet
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any of the validator's minimum gas prices. In other words, a transaction must
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provide a fee of at least one denomination that matches a validator's minimum
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gas price.
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Tendermint does not currently provide fee based mempool prioritization, and fee
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based mempool filtering is local to node and not part of consensus. But with
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minimum gas prices set, such a mechanism could be implemented by node operators.
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Because the market value for tokens will fluctuate, validators are expected to
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dynamically adjust their minimum gas prices to a level that would encourage the
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use of the network.
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