anvil/eth/
fees.rs

1use std::{
2    collections::BTreeMap,
3    fmt,
4    pin::Pin,
5    sync::Arc,
6    task::{Context, Poll},
7};
8
9use alloy_consensus::Header;
10use alloy_eips::{
11    calc_next_block_base_fee, eip1559::BaseFeeParams, eip7691::MAX_BLOBS_PER_BLOCK_ELECTRA,
12    eip7840::BlobParams,
13};
14use alloy_primitives::B256;
15use anvil_core::eth::transaction::TypedTransaction;
16use futures::StreamExt;
17use parking_lot::{Mutex, RwLock};
18use revm::{context_interface::block::BlobExcessGasAndPrice, primitives::hardfork::SpecId};
19
20use crate::eth::{
21    backend::{info::StorageInfo, notifications::NewBlockNotifications},
22    error::BlockchainError,
23};
24
25/// Maximum number of entries in the fee history cache
26pub const MAX_FEE_HISTORY_CACHE_SIZE: u64 = 2048u64;
27
28/// Initial base fee for EIP-1559 blocks.
29pub const INITIAL_BASE_FEE: u64 = 1_000_000_000;
30
31/// Initial default gas price for the first block
32pub const INITIAL_GAS_PRICE: u128 = 1_875_000_000;
33
34/// Bounds the amount the base fee can change between blocks.
35pub const BASE_FEE_CHANGE_DENOMINATOR: u128 = 8;
36
37/// Minimum suggested priority fee
38pub const MIN_SUGGESTED_PRIORITY_FEE: u128 = 1e9 as u128;
39
40pub fn default_elasticity() -> f64 {
41    1f64 / BaseFeeParams::ethereum().elasticity_multiplier as f64
42}
43
44/// Stores the fee related information
45#[derive(Clone, Debug)]
46pub struct FeeManager {
47    /// Hardfork identifier
48    spec_id: SpecId,
49    /// Tracks the base fee for the next block post London
50    ///
51    /// This value will be updated after a new block was mined
52    base_fee: Arc<RwLock<u64>>,
53    /// Whether the minimum suggested priority fee is enforced
54    is_min_priority_fee_enforced: bool,
55    /// Tracks the excess blob gas, and the base fee, for the next block post Cancun
56    ///
57    /// This value will be updated after a new block was mined
58    blob_excess_gas_and_price: Arc<RwLock<BlobExcessGasAndPrice>>,
59    /// The base price to use Pre London
60    ///
61    /// This will be constant value unless changed manually
62    gas_price: Arc<RwLock<u128>>,
63    elasticity: Arc<RwLock<f64>>,
64}
65
66impl FeeManager {
67    pub fn new(
68        spec_id: SpecId,
69        base_fee: u64,
70        is_min_priority_fee_enforced: bool,
71        gas_price: u128,
72        blob_excess_gas_and_price: BlobExcessGasAndPrice,
73    ) -> Self {
74        Self {
75            spec_id,
76            base_fee: Arc::new(RwLock::new(base_fee)),
77            is_min_priority_fee_enforced,
78            gas_price: Arc::new(RwLock::new(gas_price)),
79            blob_excess_gas_and_price: Arc::new(RwLock::new(blob_excess_gas_and_price)),
80            elasticity: Arc::new(RwLock::new(default_elasticity())),
81        }
82    }
83
84    pub fn elasticity(&self) -> f64 {
85        *self.elasticity.read()
86    }
87
88    /// Returns true for post London
89    pub fn is_eip1559(&self) -> bool {
90        (self.spec_id as u8) >= (SpecId::LONDON as u8)
91    }
92
93    pub fn is_eip4844(&self) -> bool {
94        (self.spec_id as u8) >= (SpecId::CANCUN as u8)
95    }
96
97    /// Calculates the current blob gas price
98    pub fn blob_gas_price(&self) -> u128 {
99        if self.is_eip4844() { self.base_fee_per_blob_gas() } else { 0 }
100    }
101
102    pub fn base_fee(&self) -> u64 {
103        if self.is_eip1559() { *self.base_fee.read() } else { 0 }
104    }
105
106    pub fn is_min_priority_fee_enforced(&self) -> bool {
107        self.is_min_priority_fee_enforced
108    }
109
110    /// Raw base gas price
111    pub fn raw_gas_price(&self) -> u128 {
112        *self.gas_price.read()
113    }
114
115    pub fn excess_blob_gas_and_price(&self) -> Option<BlobExcessGasAndPrice> {
116        if self.is_eip4844() { Some(*self.blob_excess_gas_and_price.read()) } else { None }
117    }
118
119    pub fn base_fee_per_blob_gas(&self) -> u128 {
120        if self.is_eip4844() { self.blob_excess_gas_and_price.read().blob_gasprice } else { 0 }
121    }
122
123    /// Returns the current gas price
124    pub fn set_gas_price(&self, price: u128) {
125        let mut gas = self.gas_price.write();
126        *gas = price;
127    }
128
129    /// Returns the current base fee
130    pub fn set_base_fee(&self, fee: u64) {
131        trace!(target: "backend::fees", "updated base fee {:?}", fee);
132        let mut base = self.base_fee.write();
133        *base = fee;
134    }
135
136    /// Sets the current blob excess gas and price
137    pub fn set_blob_excess_gas_and_price(&self, blob_excess_gas_and_price: BlobExcessGasAndPrice) {
138        trace!(target: "backend::fees", "updated blob base fee {:?}", blob_excess_gas_and_price);
139        let mut base = self.blob_excess_gas_and_price.write();
140        *base = blob_excess_gas_and_price;
141    }
142
143    /// Calculates the base fee for the next block
144    pub fn get_next_block_base_fee_per_gas(
145        &self,
146        gas_used: u64,
147        gas_limit: u64,
148        last_fee_per_gas: u64,
149    ) -> u64 {
150        // It's naturally impossible for base fee to be 0;
151        // It means it was set by the user deliberately and therefore we treat it as a constant.
152        // Therefore, we skip the base fee calculation altogether and we return 0.
153        if self.base_fee() == 0 {
154            return 0;
155        }
156        calculate_next_block_base_fee(gas_used, gas_limit, last_fee_per_gas)
157    }
158
159    /// Calculates the next block blob base fee.
160    pub fn get_next_block_blob_base_fee_per_gas(&self) -> u128 {
161        alloy_eips::eip4844::calc_blob_gasprice(
162            self.blob_excess_gas_and_price.read().excess_blob_gas,
163        )
164    }
165
166    /// Calculates the next block blob excess gas, using the provided parent blob gas used and
167    /// parent blob excess gas
168    pub fn get_next_block_blob_excess_gas(&self, blob_gas_used: u64, blob_excess_gas: u64) -> u64 {
169        alloy_eips::eip4844::calc_excess_blob_gas(blob_gas_used, blob_excess_gas)
170    }
171}
172
173/// Calculate base fee for next block. [EIP-1559](https://github.com/ethereum/EIPs/blob/master/EIPS/eip-1559.md) spec
174pub fn calculate_next_block_base_fee(gas_used: u64, gas_limit: u64, base_fee: u64) -> u64 {
175    calc_next_block_base_fee(gas_used, gas_limit, base_fee, BaseFeeParams::ethereum())
176}
177
178/// An async service that takes care of the `FeeHistory` cache
179pub struct FeeHistoryService {
180    /// blob parameters for the current spec
181    blob_params: BlobParams,
182    /// incoming notifications about new blocks
183    new_blocks: NewBlockNotifications,
184    /// contains all fee history related entries
185    cache: FeeHistoryCache,
186    /// number of items to consider
187    fee_history_limit: u64,
188    /// a type that can fetch ethereum-storage data
189    storage_info: StorageInfo,
190}
191
192impl FeeHistoryService {
193    pub fn new(
194        blob_params: BlobParams,
195        new_blocks: NewBlockNotifications,
196        cache: FeeHistoryCache,
197        storage_info: StorageInfo,
198    ) -> Self {
199        Self {
200            blob_params,
201            new_blocks,
202            cache,
203            fee_history_limit: MAX_FEE_HISTORY_CACHE_SIZE,
204            storage_info,
205        }
206    }
207
208    /// Returns the configured history limit
209    pub fn fee_history_limit(&self) -> u64 {
210        self.fee_history_limit
211    }
212
213    /// Inserts a new cache entry for the given block
214    pub(crate) fn insert_cache_entry_for_block(&self, hash: B256, header: &Header) {
215        let (result, block_number) = self.create_cache_entry(hash, header);
216        self.insert_cache_entry(result, block_number);
217    }
218
219    /// Create a new history entry for the block
220    fn create_cache_entry(
221        &self,
222        hash: B256,
223        header: &Header,
224    ) -> (FeeHistoryCacheItem, Option<u64>) {
225        // percentile list from 0.0 to 100.0 with a 0.5 resolution.
226        // this will create 200 percentile points
227        let reward_percentiles: Vec<f64> = {
228            let mut percentile: f64 = 0.0;
229            (0..=200)
230                .map(|_| {
231                    let val = percentile;
232                    percentile += 0.5;
233                    val
234                })
235                .collect()
236        };
237
238        let mut block_number: Option<u64> = None;
239        let base_fee = header.base_fee_per_gas.map(|g| g as u128).unwrap_or_default();
240        let excess_blob_gas = header.excess_blob_gas.map(|g| g as u128);
241        let blob_gas_used = header.blob_gas_used.map(|g| g as u128);
242        let base_fee_per_blob_gas = header.blob_fee(self.blob_params);
243
244        let mut item = FeeHistoryCacheItem {
245            base_fee,
246            gas_used_ratio: 0f64,
247            blob_gas_used_ratio: 0f64,
248            rewards: Vec::new(),
249            excess_blob_gas,
250            base_fee_per_blob_gas,
251            blob_gas_used,
252        };
253
254        let current_block = self.storage_info.block(hash);
255        let current_receipts = self.storage_info.receipts(hash);
256
257        if let (Some(block), Some(receipts)) = (current_block, current_receipts) {
258            block_number = Some(block.header.number);
259
260            let gas_used = block.header.gas_used as f64;
261            let blob_gas_used = block.header.blob_gas_used.map(|g| g as f64);
262            item.gas_used_ratio = gas_used / block.header.gas_limit as f64;
263            item.blob_gas_used_ratio =
264                blob_gas_used.map(|g| g / MAX_BLOBS_PER_BLOCK_ELECTRA as f64).unwrap_or(0 as f64);
265
266            // extract useful tx info (gas_used, effective_reward)
267            let mut transactions: Vec<(_, _)> = receipts
268                .iter()
269                .enumerate()
270                .map(|(i, receipt)| {
271                    let gas_used = receipt.cumulative_gas_used();
272                    let effective_reward = match block.transactions.get(i).map(|tx| &tx.transaction)
273                    {
274                        Some(TypedTransaction::Legacy(t)) => {
275                            t.tx().gas_price.saturating_sub(base_fee)
276                        }
277                        Some(TypedTransaction::EIP2930(t)) => {
278                            t.tx().gas_price.saturating_sub(base_fee)
279                        }
280                        Some(TypedTransaction::EIP1559(t)) => t
281                            .tx()
282                            .max_priority_fee_per_gas
283                            .min(t.tx().max_fee_per_gas.saturating_sub(base_fee)),
284                        // TODO: This probably needs to be extended to extract 4844 info.
285                        Some(TypedTransaction::EIP4844(t)) => t
286                            .tx()
287                            .tx()
288                            .max_priority_fee_per_gas
289                            .min(t.tx().tx().max_fee_per_gas.saturating_sub(base_fee)),
290                        Some(TypedTransaction::EIP7702(t)) => t
291                            .tx()
292                            .max_priority_fee_per_gas
293                            .min(t.tx().max_fee_per_gas.saturating_sub(base_fee)),
294                        Some(TypedTransaction::Deposit(_)) => 0,
295                        None => 0,
296                    };
297
298                    (gas_used, effective_reward)
299                })
300                .collect();
301
302            // sort by effective reward asc
303            transactions.sort_by(|(_, a), (_, b)| a.cmp(b));
304
305            // calculate percentile rewards
306            item.rewards = reward_percentiles
307                .into_iter()
308                .filter_map(|p| {
309                    let target_gas = (p * gas_used / 100f64) as u64;
310                    let mut sum_gas = 0;
311                    for (gas_used, effective_reward) in transactions.iter().copied() {
312                        sum_gas += gas_used;
313                        if target_gas <= sum_gas {
314                            return Some(effective_reward);
315                        }
316                    }
317                    None
318                })
319                .collect();
320        } else {
321            item.rewards = reward_percentiles.iter().map(|_| 0).collect();
322        }
323        (item, block_number)
324    }
325
326    fn insert_cache_entry(&self, item: FeeHistoryCacheItem, block_number: Option<u64>) {
327        if let Some(block_number) = block_number {
328            trace!(target: "fees", "insert new history item={:?} for {}", item, block_number);
329            let mut cache = self.cache.lock();
330            cache.insert(block_number, item);
331
332            // adhere to cache limit
333            let pop_next = block_number.saturating_sub(self.fee_history_limit);
334
335            let num_remove = (cache.len() as u64).saturating_sub(self.fee_history_limit);
336            for num in 0..num_remove {
337                let key = pop_next - num;
338                cache.remove(&key);
339            }
340        }
341    }
342}
343
344// An endless future that listens for new blocks and updates the cache
345impl Future for FeeHistoryService {
346    type Output = ();
347
348    fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
349        let pin = self.get_mut();
350
351        while let Poll::Ready(Some(notification)) = pin.new_blocks.poll_next_unpin(cx) {
352            // add the imported block.
353            pin.insert_cache_entry_for_block(notification.hash, notification.header.as_ref());
354        }
355
356        Poll::Pending
357    }
358}
359
360pub type FeeHistoryCache = Arc<Mutex<BTreeMap<u64, FeeHistoryCacheItem>>>;
361
362/// A single item in the whole fee history cache
363#[derive(Clone, Debug)]
364pub struct FeeHistoryCacheItem {
365    pub base_fee: u128,
366    pub gas_used_ratio: f64,
367    pub base_fee_per_blob_gas: Option<u128>,
368    pub blob_gas_used_ratio: f64,
369    pub excess_blob_gas: Option<u128>,
370    pub blob_gas_used: Option<u128>,
371    pub rewards: Vec<u128>,
372}
373
374#[derive(Clone, Default)]
375pub struct FeeDetails {
376    pub gas_price: Option<u128>,
377    pub max_fee_per_gas: Option<u128>,
378    pub max_priority_fee_per_gas: Option<u128>,
379    pub max_fee_per_blob_gas: Option<u128>,
380}
381
382impl FeeDetails {
383    /// All values zero
384    pub fn zero() -> Self {
385        Self {
386            gas_price: Some(0),
387            max_fee_per_gas: Some(0),
388            max_priority_fee_per_gas: Some(0),
389            max_fee_per_blob_gas: None,
390        }
391    }
392
393    /// If neither `gas_price` nor `max_fee_per_gas` is `Some`, this will set both to `0`
394    pub fn or_zero_fees(self) -> Self {
395        let Self { gas_price, max_fee_per_gas, max_priority_fee_per_gas, max_fee_per_blob_gas } =
396            self;
397
398        let no_fees = gas_price.is_none() && max_fee_per_gas.is_none();
399        let gas_price = if no_fees { Some(0) } else { gas_price };
400        let max_fee_per_gas = if no_fees { Some(0) } else { max_fee_per_gas };
401        let max_fee_per_blob_gas = if no_fees { None } else { max_fee_per_blob_gas };
402
403        Self { gas_price, max_fee_per_gas, max_priority_fee_per_gas, max_fee_per_blob_gas }
404    }
405
406    /// Turns this type into a tuple
407    pub fn split(self) -> (Option<u128>, Option<u128>, Option<u128>, Option<u128>) {
408        let Self { gas_price, max_fee_per_gas, max_priority_fee_per_gas, max_fee_per_blob_gas } =
409            self;
410        (gas_price, max_fee_per_gas, max_priority_fee_per_gas, max_fee_per_blob_gas)
411    }
412
413    /// Creates a new instance from the request's gas related values
414    pub fn new(
415        request_gas_price: Option<u128>,
416        request_max_fee: Option<u128>,
417        request_priority: Option<u128>,
418        max_fee_per_blob_gas: Option<u128>,
419    ) -> Result<Self, BlockchainError> {
420        match (request_gas_price, request_max_fee, request_priority, max_fee_per_blob_gas) {
421            (gas_price, None, None, None) => {
422                // Legacy request, all default to gas price.
423                Ok(Self {
424                    gas_price,
425                    max_fee_per_gas: gas_price,
426                    max_priority_fee_per_gas: gas_price,
427                    max_fee_per_blob_gas: None,
428                })
429            }
430            (_, max_fee, max_priority, None) => {
431                // eip-1559
432                // Ensure `max_priority_fee_per_gas` is less or equal to `max_fee_per_gas`.
433                if let Some(max_priority) = max_priority {
434                    let max_fee = max_fee.unwrap_or_default();
435                    if max_priority > max_fee {
436                        return Err(BlockchainError::InvalidFeeInput);
437                    }
438                }
439                Ok(Self {
440                    gas_price: max_fee,
441                    max_fee_per_gas: max_fee,
442                    max_priority_fee_per_gas: max_priority,
443                    max_fee_per_blob_gas: None,
444                })
445            }
446            (_, max_fee, max_priority, max_fee_per_blob_gas) => {
447                // eip-1559
448                // Ensure `max_priority_fee_per_gas` is less or equal to `max_fee_per_gas`.
449                if let Some(max_priority) = max_priority {
450                    let max_fee = max_fee.unwrap_or_default();
451                    if max_priority > max_fee {
452                        return Err(BlockchainError::InvalidFeeInput);
453                    }
454                }
455                Ok(Self {
456                    gas_price: max_fee,
457                    max_fee_per_gas: max_fee,
458                    max_priority_fee_per_gas: max_priority,
459                    max_fee_per_blob_gas,
460                })
461            }
462        }
463    }
464}
465
466impl fmt::Debug for FeeDetails {
467    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
468        write!(fmt, "Fees {{ ")?;
469        write!(fmt, "gas_price: {:?}, ", self.gas_price)?;
470        write!(fmt, "max_fee_per_gas: {:?}, ", self.max_fee_per_gas)?;
471        write!(fmt, "max_priority_fee_per_gas: {:?}, ", self.max_priority_fee_per_gas)?;
472        write!(fmt, "}}")?;
473        Ok(())
474    }
475}
anvil/eth/fees.rs

anvil/eth/
fees.rs
