연산 비용(Computation Cost)

Since Klaytn aims to maintain 1-second block time, the execution time of transactions have to be managed. Here are three approaches to achieve that:

  1. Limiting the gas limit of a transaction 2. Limiting the execution time of a transaction 3. Limiting the computation cost of a transaction

Limiting the gas limit of a transaction was not a feasible solution because the concept of the gas represents the current exchange value of the various resources in the blockchain platform such as computation, storage, network bandwidth, and so on. 따라서, 트랜잭션 실행 시간을 관리하기 위한 방법으로는 적합하지 않습니다.

Limiting the execution time of a transaction was not feasible either because the execution time can vary between nodes on the blockchain platform. For example, consider the case in which we limit the execution time of a transaction to be 100 milli-second. 만약 한 노드에서 트랜잭션 실행 시간이 90ms고, 다른 노드에서 110ms라면 두 노드는 합의에 도달 할 수 없습니다. Hence, this solution is not appropriate.

The last approoach is to limit the computation cost of a transaction. We modelled the computation cost of each EVM opcode based on its actual execution time and limit the sum of computation cost of a transaction. 이 접근 방식을 사용하면 다른 요소들을 제거하고, 정규화된 실행 시간만 계산하여 노드들이 합의에 도달 할 수 있습니다.

Therefore, we chose the third option for Klaytn. 현재는 실행 비용 한도는 100,000,000으로 설정되어 있습니다. Since the limit is determined by the platform, developers should be aware of the computation cost of a transaction. To calculate the computation cost of a transaction, Klaytn provides klay_estimateComputationCost. 사용법은 klay_estimateGas와 거의 같습니다.

Opcode의 연산 비용

아래 표는 EVM Opcode의 연산 비용을 보여줍니다. 연산 비용은 시뮬레이션을 통해 결정되었습니다.

Opcode

연산 비용

STOP

0

ADD

150

MUL

200

SUB

219

DIV

404

SDIV

739

MOD

812

SMOD

560

ADDMOD

3349

MULMOD

4757

EXP

5000

SIGNEXTEND

481

LT

201

GT

264

SLT

176

SGT

222

EQ

220

ISZERO

165

AND

288

OR

160

XOR

657

NOT

1289

BYTE

589

SHL

1603

SHR

1346

SAR

1815

SHA3

2465

ADDRESS

284

BALANCE

1407

ORIGIN

210

CALLER

188

CALLVALUE

149

CALLDATALOAD

596

CALLDATASIZE

194

CALLDATACOPY

100

CODESIZE

145

CODECOPY

898

GASPRICE

131

EXTCODESIZE

1481

EXTCODECOPY

1000

RETURNDATASIZE

10

RETURNDATACOPY

40

EXTCODEHASH

1000

BLOCKHASH

500

COINBASE

189

TIMESTAMP

265

NUMBER

202

DIFFICULTY

180

GASLIMIT

166

POP

140

MLOAD

376

MSTORE

288

MSTORE8

5142

SLOAD

835

SSTORE

1548

JUMP

253

JUMPI

176

PC

147

MSIZE

137

GAS

230

JUMPDEST

10

PUSH1

120

PUSH2

120

PUSH3

120

PUSH4

120

PUSH5

120

PUSH6

120

PUSH7

120

PUSH8

120

PUSH9

120

PUSH10

120

PUSH11

120

PUSH12

120

PUSH13

120

PUSH14

120

PUSH15

120

PUSH16

120

PUSH17

120

PUSH18

120

PUSH19

120

PUSH20

120

PUSH21

120

PUSH22

120

PUSH23

120

PUSH24

120

PUSH25

120

PUSH26

120

PUSH27

120

PUSH28

120

PUSH29

120

PUSH30

120

PUSH31

120

PUSH32

120

DUP1

190

DUP2

190

DUP3

176

DUP4

142

DUP5

177

DUP6

165

DUP7

147

DUP8

157

DUP9

138

DUP10

174

DUP11

141

DUP12

144

DUP13

157

DUP14

143

DUP15

237

DUP16

149

SWAP1

141

SWAP2

156

SWAP3

145

SWAP4

135

SWAP5

115

SWAP6

146

SWAP7

199

SWAP8

130

SWAP9

160

SWAP10

134

SWAP11

147

SWAP12

128

SWAP13

121

SWAP14

114

SWAP15

197

SWAP16

128

LOG0

100

LOG1

1000

LOG2

1000

LOG3

1000

LOG4

1000

PUSH

0

DUP

0

SWAP

0

CREATE

2094

CALL

5000

CALLCODE

4000

RETURN

0

DELEGATECALL

696

CREATE2

10000

STATICCALL

10000

REVERT

0

SELFDESTRUCT

0