anvil feat: support forking at transaction level

[ChinW]

Component

Anvil

Describe the feature you would like

hi team, like #3262

would like also have this feature in anvil project, also happy with some guidance to contribute back.

by the way, I would like to confirm my below understanding of forking:

I am forking eth network with block number by using private eth full node, found out multicall is very slow in this environment (couple minutes, > 5 minutes), while same calls on latest block number (no forking) is very very fast (<1 minute).

Is it because inside the box, the local forking node is actually requesting the remote full node with lots of getStorageAt request, so that make it slow. If true, I guess if I put the local forking test program into the full node machine, it should be much much faster. Is my understanding correct?

Additional context

No response

[mattsse]

we already have this functionality in forge, which we could also enable in anvil

I am forking eth network with block number by using private eth full node, found out multicall is very slow in this environment (couple minutes, > 5 minutes), while same calls on latest block number (no forking) is very very fast (<1 minute).

if you're using a local node without any rate limits, ptal at the --no-rate-limit setting

[dhiraj0911]

@ChinW can you assign this issue to me

[ChinW]

@mattsse hi, I wonder if you know, when using vm.createSelectFork(rpcUrl, vm.parseBytes32(txId)), will this also apply rate-limit at default? I didnt see how to disable rate limit by vm.XXXXX function

[mattsse]

good point, this currently does not use the no rate limit option

foundry/crates/evm/src/executor/fork/multi.rs

Lines 474 to 488 in cdba273

	/// Creates a new fork
	///
	/// This will establish a new `Provider` to the endpoint and return the Fork Backend
	async fn create_fork(
	mut fork: CreateFork,
	retries: u32,
	backoff: u64,
	) -> eyre::Result<(CreatedFork, Handler)> {
	let provider = Arc::new(
	ProviderBuilder::new(fork.url.as_str())
	.max_retry(retries)
	.initial_backoff(backoff)
	.compute_units_per_second(fork.evm_opts.get_compute_units_per_second())
	.build()?,
	);

foundry/crates/evm/src/executor/fork/multi.rs

Lines 276 to 279 in cdba273

	let retries = self.retries;
	let backoff = self.backoff;
	// need to create a new fork
	let task = Box::pin(create_fork(fork, retries, backoff));

and uses fixed values for some reason

foundry/crates/evm/src/executor/fork/multi.rs

Lines 235 to 237 in cdba273

	retries: 8,
	// 800ms
	backoff: 800,

we definitely want support for this, I think the easiest way would be to use the values of the CreateFork argument instead here

foundry/crates/evm/src/executor/fork/multi.rs

Line 262 in cdba273

fn create_fork(&mut self, fork: CreateFork, sender: CreateSender) {

via createfork.evm_opts.no_rpc_rate_limit

this would be an easy fix, do you want to take this @ChinW ?

converting this into an issue