Linked Questions

145
votes
2answers
28k views

What is the difference between a transaction and a call?

What is the difference between a transaction and a call? In some interfaces, I can interact with contracts via calls or via transactions. What is the difference between the two, and can contracts also ...
88
votes
2answers
50k views

Which cryptographic hash function does Ethereum use?

Many sources refer to the use of the "SHA3" cryptographic hash function within Ethereum, but the Ethereum project began before the SHA3 standard was finalised, and there was some confusion/controversy ...
22
votes
2answers
15k views

How do I know how much gas to use when calling a contract?

When I am calling (sending a transaction to) a contract how do I determine how much gas to use? Is there a way to calculate this upfront & what happens if I send too much / too few gas?
14
votes
3answers
10k views

Is it possible to build a private (permissioned) blockchain with Ethereum?

Ethereum is a great blockchain, but for some services the transaction fee is prohibitively too expensive. Is there any project and/or guideline on making Ethereum so it works on permissioned ...
12
votes
2answers
710 views

Why does Ethereum have gas?

Why does Ethereum have gas? What other approaches could Ethereum have used to work around the Halting Problem?
10
votes
2answers
21k views

How to calculate transaction fee?

For calculating the transaction fee using web3js I am using it's gas price: eth.getTransaction("txhash").gasPrice multiplied by how much gas was actually used: eth.getTransactionReceipt("txhash")....
8
votes
1answer
992 views

Can a transaction get lost?

Given that I am connected to the network with at least one peer, can I be sure that a transaction I sent will be executed (either with fail or success)? Is there a possibility that it will never make ...
7
votes
2answers
2k views

Who gets the fee from contract call?

Basically you don't need to pay fee for contract call, but if a contract method does lots of work, you need to add gas in contract call to prevent DoS attack like this: contract.method.call({gas: ...
5
votes
1answer
972 views

What's the difference in the ways of calling a contract function?

After I get an instance of a contract, there are 3 ways to call the contract function below: 1.testInstance.testfunc({from:eth.accounts[0]}) 2.testInstance.testfunc.sendTransaction({from:eth.accounts[...
4
votes
3answers
134 views

Can a “forward” smart contract forward the received ether to another “forward” smart contract which forwards it to an address?

I am pretty new to solidity. I am trying to create a smart contract which deploys another smart contract and transfers ether to the newly created contract when a payment greater than 0.01 ether is ...
4
votes
2answers
136 views

Call Smart Contract every 5 Second

Is it possible the call a method of a smart contract every 5 seconds? Lets say i want to call a webservice or an other smart contract in order to get the actual value? That is not possible or? In ...
4
votes
1answer
4k views

How to Set Gas Price in Private Blockchain?

I admit that I don't understand Gas at all. But I think it is basically the currency which dapps use to interact with each other and the blockchain. Yes? If you're creating a custom/private network,...
4
votes
1answer
2k views

Where exactly do DApps run? Who gets rewarded for running them? [duplicate]

So I am currently running a full node, as well as a GPU miner. I am curious first of all where do DApps get run? They wouldn't make sense to run on a GPU as they aren't very parallizable, so I am ...
3
votes
3answers
4k views

What is the point of variable transaction fees in Ethereum (and Bitcoin as well)?

After reading through the docs and through this post, I understand the concept and need for gas, but I do not understand why each transaction can have a variable fee associated with it. It seems to be ...
3
votes
1answer
664 views

what is difference between “gas” “gas price” and “fee”?

Can we say that gas is the unit of transaction fee ? And gas price is the same transaction fee ? If so, why we do not use ether and wei instead of gas ?
3
votes
1answer
1k views

When calling a smart contract function, who gets paid and how much does the caller pay?

This is an extended question to What is "gas" and transaction fee in Ethereum?. Who gets paid and how much does the caller pay? Let's make some assumptions: There is a function F which ...
2
votes
2answers
3k views

If the price of ether coin goes up, does it mean less likely people are going to build application on the ethereum network?

If I am not mistaking, application developers need to pay using ether coins to have their application hosted on the ethereum network. So if the price of ether keeps going up like it is now, doesn't it ...
2
votes
2answers
16k views

How much is 1 gas in ether? [duplicate]

On Etherscan the daily GasUsed chart shows current usage of 10-15 bill. How do I convert this correctly to ether (ETH)?.
2
votes
2answers
656 views

why are Transactions paid in Gas and not just Ether directly [duplicate]

All the explanations I heard for the Gas usage, could imho also be dealt with in Ether directly. What is it that Gas does that couldn't be done with Ether directly?
2
votes
1answer
31 views

Should I pre-buy gas to effect ethereum transaction?

I am new to ethereum. I have a few questions. Should I pre-buy gas to effect ethereum transactions? Or can I just set what is the gas price I am willing to pay so that at the time of transaction the ...
2
votes
1answer
454 views

EVM opcodes-prices

1) Why are opcodes in Ethereum priced the way they are priced and why is the EVM so expensive? 2) Right upfront, I do not say that it is too expensive to perform a tx on Ethereum, I just say that ...
2
votes
1answer
331 views

Digital asset management dapp using Ethereum

I am new to ethereum and also I have tried out some examples for building smart contract using truffle and ganache. But I want to make Digital asset management dapp using ethereum. Like, if have I ...
2
votes
2answers
542 views

ERC20 Transaction Fee - setFeeCurrency

Hi i now read everywhere that a transaction fee has to be paid in ETH. But I also found via the ethereum page the following page: https://github.com/ethereum/wiki/wiki/Standardized_Contract_APIs#...
2
votes
1answer
242 views

Solidity browser compiler crashes

It seems like every time I try to execute a contract function through the browser compiler that requires more than around 50k gas (give or take) to execute, the browser tab's memory gets to around 1GB ...
1
vote
3answers
67 views

Can blockchain technology can ever be useful if the currency conversion to fiat money is volatile? [closed]

From my limited understanding of blockchain technology in general and ethereum in particular, whatever the token, or ether that this technology uses, eventually it has to be related to fiat money. Eg: ...
1
vote
2answers
228 views

Why is my account balance after executing the contract so different?

I'm writing a test for a Lottery contract: var Lottery = artifacts.require("./Lottery.sol"); contract('Lottery', function (accounts) { var ACC_FABIAN = accounts[0]; var ACC_RENE = accounts[1]...
1
vote
1answer
99 views

What would be the cost of this transaction to end user?

A simple question on gas spent on a transaction here. I'm experimenting with testnet transaction on a simple contract that stores a value, trying to figure out how much a client would pay. What would ...
1
vote
1answer
94 views

How to do performance evaluation?

How to do the performance evaluation in terms of secs or minutes? what is the command to use in solidity?
1
vote
1answer
48 views

Transaction fees in ethereum [duplicate]

I have created an ERC20 token, but whenever I want to trnasfer it, transaction fees is deducted in ethers. But I donot want to but ethers. Cant the fee be deducted in terms of my custom token? Thanks
1
vote
0answers
42 views

What's the point in the 'gas' parameter passed to function 'signTransaction'? [duplicate]

I am using web3.js v1 in order to sign and send transactions: async function signAndSend(transaction) { let options = { to : transaction._parent._address, data: transaction....
1
vote
0answers
25 views

Does only one miner collect my transaction fee? [duplicate]

I just ran in to the concept of gas and found this community. This question and answer were particularly helpful, but they leave one thing unanswered for me: If I send out a transaction with a given ...
0
votes
2answers
345 views

GAS price structure

how to decide gas price while writing smart contract ? and how to know how much gas is going to be used while each token transaction ? and on https://ethgasstation.info/ mentioned price is ...
0
votes
1answer
378 views

Are transactions really instant?

I am new to blockchain in general and still trying to nail down some basic concepts, this being one of them: if a new block is added to the chain approximately every 10 minutes, does that mean a ...
0
votes
1answer
226 views

Is the gas-limit as seen on ethstats measured in wei?

Simple question but I can't seem to find the answer online
0
votes
2answers
52 views

Why is a failed transaction included in the blockchain as a “failed transaction”

According to this highest upvoted answer, "but still include it in the blockchain as a "failed transaction"... What is meant by the term "gas"?
0
votes
2answers
37 views

Does price of smart contract execution raise with price of ethereum

I can't determine properly whether higher price of ETH means smart contracts will also cost higher(in fiat not eth) and is it reciprocal, like if we have a SC deployed and eth price raises 10x, will ...
0
votes
2answers
22 views

If Ethereum gas charges based on the individual CPU instructions

I'm trying to understand exactly how gas works. Wondering if it charges based on actual individual CPU instructions (like Assembly-level x86 instruction set architecture level of detail), or if it ...
0
votes
1answer
37 views

How do i know how much eth the receiver will get?

I bought some ethereum a long time ago and I'm trying to buy something with it now. I want to make sure the address I'm sending it to gets a specific amount (say 2.00 ETH). When I enter the "amount to ...
0
votes
2answers
53 views

What is the function of Ether in operating an application on the Ethereum blockchain? [duplicate]

What is the relationship between the price of Ether and the usage of the Ethereuem blockchain? Or is a Ether coin simply a means of holding a piece of the value of the Ethereum blockchain (like a ...
0
votes
1answer
186 views

How does gas in Ethereum works? [duplicate]

Let say I have a code that print "Hello World". I deploy it to the blockchain and pay 1000 gas for it. Will my code keep running for every subsequent block till it runs out of gas? Or will it only run ...
0
votes
2answers
715 views

When Ethereum price goes up does complexity go up too?

And what is their relationship? Is it linear, exponential. For example, if ether were to double in price tomorrow, does that mean the complexity is twice as much, or... ?
0
votes
1answer
64 views

What is the meaning of “Gas Used” on ethgasstation.info?

It's rather confusing cos when I googled "gas used" I don't get any exact result, NOT even from ethgasstation.info and most people are talking about transaction price, gas limit, etc. So, does "gas ...
0
votes
1answer
47 views

Execution gas cost

I use web3 and truffle to get info about my testnet transactions. There are few fields about gas used per transaction, such as: gasPrice, gas, gasUsed. But how to get field 'execution cost'?
0
votes
1answer
120 views

What is the unit of measurement used in GasPrice and GasLimit?

I did a check, in ethgasstation the current safeLow = 15GWei, which is equal = 15,000,000,000 wei However, when I issue eth.getBlock("latest") what I get was: > eth.getBlock("latest") { ...
0
votes
1answer
2k views

myetherwallet.com is taking forever [duplicate]

I sent a transaction over 6 hours ago from myetherwallet to an outside address with the site's suggested 21000 gas limit. Its up to over 1000 block confirmations but still has not completed, yet ...