// Copyright 2014 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package core
import (
"errors"
"fmt"
"math"
"math/big"
"sort"
"sync"
"time"
"github.com/dexon-foundation/dexon/common"
"github.com/dexon-foundation/dexon/common/prque"
"github.com/dexon-foundation/dexon/core/state"
"github.com/dexon-foundation/dexon/core/types"
"github.com/dexon-foundation/dexon/event"
"github.com/dexon-foundation/dexon/log"
"github.com/dexon-foundation/dexon/metrics"
"github.com/dexon-foundation/dexon/params"
)
const (
// chainHeadChanSize is the size of channel listening to ChainHeadEvent.
chainHeadChanSize = 10
// blockConfirmedChanSize is the size of channel listening to BlockConfirmedEvent.
blockConfirmedChanSize = 10
)
var (
// ErrInvalidSender is returned if the transaction contains an invalid signature.
ErrInvalidSender = errors.New("invalid sender")
// ErrNonceTooLow is returned if the nonce of a transaction is lower than the
// one present in the local chain.
ErrNonceTooLow = errors.New("nonce too low")
// ErrUnderpriced is returned if a transaction's gas price is below the minimum
// configured for the transaction pool.
ErrUnderpriced = errors.New("transaction underpriced")
// ErrReplaceUnderpriced is returned if a transaction is attempted to be replaced
// with a different one without the required price bump.
ErrReplaceUnderpriced = errors.New("replacement transaction underpriced")
// ErrInsufficientFunds is returned if the total cost of executing a transaction
// is higher than the balance of the user's account.
ErrInsufficientFunds = errors.New("insufficient funds for gas * price + value")
// ErrIntrinsicGas is returned if the transaction is specified to use less gas
// than required to start the invocation.
ErrIntrinsicGas = errors.New("intrinsic gas too low")
// ErrGasLimit is returned if a transaction's requested gas limit exceeds the
// maximum allowance of the current block.
ErrGasLimit = errors.New("exceeds block gas limit")
// ErrNegativeValue is a sanity error to ensure noone is able to specify a
// transaction with a negative value.
ErrNegativeValue = errors.New("negative value")
// ErrOversizedData is returned if the input data of a transaction is greater
// than some meaningful limit a user might use. This is not a consensus error
// making the transaction invalid, rather a DOS protection.
ErrOversizedData = errors.New("oversized data")
)
var (
evictionInterval = time.Minute // Time interval to check for evictable transactions
statsReportInterval = 8 * time.Second // Time interval to report transaction pool stats
)
var (
// Metrics for the pending pool
pendingDiscardCounter = metrics.NewRegisteredCounter("txpool/pending/discard", nil)
pendingReplaceCounter = metrics.NewRegisteredCounter("txpool/pending/replace", nil)
pendingRateLimitCounter = metrics.NewRegisteredCounter("txpool/pending/ratelimit", nil) // Dropped due to rate limiting
pendingNofundsCounter = metrics.NewRegisteredCounter("txpool/pending/nofunds", nil) // Dropped due to out-of-funds
// Metrics for the queued pool
queuedDiscardCounter = metrics.NewRegisteredCounter("txpool/queued/discard", nil)
queuedReplaceCounter = metrics.NewRegisteredCounter("txpool/queued/replace", nil)
queuedRateLimitCounter = metrics.NewRegisteredCounter("txpool/queued/ratelimit", nil) // Dropped due to rate limiting
queuedNofundsCounter = metrics.NewRegisteredCounter("txpool/queued/nofunds", nil) // Dropped due to out-of-funds
// General tx metrics
invalidTxCounter = metrics.NewRegisteredCounter("txpool/invalid", nil)
underpricedTxCounter = metrics.NewRegisteredCounter("txpool/underpriced", nil)
)
// TxStatus is the current status of a transaction as seen by the pool.
type TxStatus uint
const (
TxStatusUnknown TxStatus = iota
TxStatusQueued
TxStatusPending
TxStatusIncluded
)
// blockChain provides the state of blockchain and current gas limit to do
// some pre checks in tx pool and event subscribers.
type blockChain interface {
CurrentBlock() *types.Block
GetBlock(hash common.Hash, number uint64) *types.Block
StateAt(root common.Hash) (*state.StateDB, error)
SubscribeChainHeadEvent(ch chan<- ChainHeadEvent) event.Subscription
SubscribeBlockConfirmedEvent(ch chan<- BlockConfirmedEvent) event.Subscription
}
// TxPoolConfig are the configuration parameters of the transaction pool.
type TxPoolConfig struct {
Locals []common.Address // Addresses that should be treated by default as local
NoLocals bool // Whether local transaction handling should be disabled
Journal string // Journal of local transactions to survive node restarts
Rejournal time.Duration // Time interval to regenerate the local transaction journal
PriceLimit uint64 // Minimum gas price to enforce for acceptance into the pool
PriceBump uint64 // Minimum price bump percentage to replace an already existing transaction (nonce)
AccountSlots uint64 // Number of executable transaction slots guaranteed per account
GlobalSlots uint64 // Maximum number of executable transaction slots for all accounts
AccountQueue uint64 // Maximum number of non-executable transaction slots permitted per account
GlobalQueue uint64 // Maximum number of non-executable transaction slots for all accounts
Lifetime time.Duration // Maximum amount of time non-executable transaction are queued
}
// DefaultTxPoolConfig contains the default configurations for the transaction
// pool.
var DefaultTxPoolConfig = TxPoolConfig{
Journal: "transactions.rlp",
Rejournal: time.Hour,
PriceLimit: 1,
PriceBump: 10,
AccountSlots: 512,
GlobalSlots: 40960,
AccountQueue: 1024,
GlobalQueue: 20240,
Lifetime: 3 * time.Hour,
}
// sanitize checks the provided user configurations and changes anything that's
// unreasonable or unworkable.
func (config *TxPoolConfig) sanitize() TxPoolConfig {
conf := *config
if conf.Rejournal < time.Second {
log.Warn("Sanitizing invalid txpool journal time", "provided", conf.Rejournal, "updated", time.Second)
conf.Rejournal = time.Second
}
if conf.PriceLimit < 1 {
log.Warn("Sanitizing invalid txpool price limit", "provided", conf.PriceLimit, "updated", DefaultTxPoolConfig.PriceLimit)
conf.PriceLimit = DefaultTxPoolConfig.PriceLimit
}
if conf.PriceBump < 1 {
log.Warn("Sanitizing invalid txpool price bump", "provided", conf.PriceBump, "updated", DefaultTxPoolConfig.PriceBump)
conf.PriceBump = DefaultTxPoolConfig.PriceBump
}
if conf.AccountSlots < 1 {
log.Warn("Sanitizing invalid txpool account slots", "provided", conf.AccountSlots, "updated", DefaultTxPoolConfig.AccountSlots)
conf.AccountSlots = DefaultTxPoolConfig.AccountSlots
}
if conf.GlobalSlots < 1 {
log.Warn("Sanitizing invalid txpool global slots", "provided", conf.GlobalSlots, "updated", DefaultTxPoolConfig.GlobalSlots)
conf.GlobalSlots = DefaultTxPoolConfig.GlobalSlots
}
if conf.AccountQueue < 1 {
log.Warn("Sanitizing invalid txpool account queue", "provided", conf.AccountQueue, "updated", DefaultTxPoolConfig.AccountQueue)
conf.AccountQueue = DefaultTxPoolConfig.AccountQueue
}
if conf.GlobalQueue < 1 {
log.Warn("Sanitizing invalid txpool global queue", "provided", conf.GlobalQueue, "updated", DefaultTxPoolConfig.GlobalQueue)
conf.GlobalQueue = DefaultTxPoolConfig.GlobalQueue
}
if conf.Lifetime < 1 {
log.Warn("Sanitizing invalid txpool lifetime", "provided", conf.Lifetime, "updated", DefaultTxPoolConfig.Lifetime)
conf.Lifetime = DefaultTxPoolConfig.Lifetime
}
return conf
}
// TxPool contains all currently known transactions. Transactions
// enter the pool when they are received from the network or submitted
// locally. They exit the pool when they are included in the blockchain.
//
// The pool separates processable transactions (which can be applied to the
// current state) and future transactions. Transactions move between those
// two states over time as they are received and processed.
type TxPool struct {
config TxPoolConfig
chainconfig *params.ChainConfig
chain blockChain
gasPrice *big.Int
txFeed event.Feed
scope event.SubscriptionScope
chainHeadCh chan ChainHeadEvent
chainHeadSub event.Subscription
blockConfirmedCh chan BlockConfirmedEvent
blockConfirmedSub event.Subscription
signer types.Signer
mu sync.RWMutex
currentState *state.StateDB // Current state in the blockchain head
pendingState *state.ManagedState // Pending state tracking virtual nonces
currentMaxGas uint64 // Current gas limit for transaction caps
locals *accountSet // Set of local transaction to exempt from eviction rules
journal *txJournal // Journal of local transaction to back up to disk
pending map[common.Address]*txList // All currently processable transactions
queue map[common.Address]*txList // Queued but non-processable transactions
beats map[common.Address]time.Time // Last heartbeat from each known account
all *txLookup // All transactions to allow lookups
priced *txPricedList // All transactions sorted by price
wg sync.WaitGroup // for shutdown sync
homestead bool
isBlockProposer bool
}
// NewTxPool creates a new transaction pool to gather, sort and filter inbound
// transactions from the network.
func NewTxPool(config TxPoolConfig, chainconfig *params.ChainConfig, chain blockChain, isBlockProposer bool) *TxPool {
// Sanitize the input to ensure no vulnerable gas prices are set
config = (&config).sanitize()
// Create the transaction pool with its initial settings
pool := &TxPool{
config: config,
chainconfig: chainconfig,
chain: chain,
signer: types.NewEIP155Signer(chainconfig.ChainID),
pending: make(map[common.Address]*txList),
queue: make(map[common.Address]*txList),
beats: make(map[common.Address]time.Time),
all: newTxLookup(),
chainHeadCh: make(chan ChainHeadEvent, chainHeadChanSize),
blockConfirmedCh: make(chan BlockConfirmedEvent, blockConfirmedChanSize),
gasPrice: new(big.Int).SetUint64(config.PriceLimit),
isBlockProposer: isBlockProposer,
}
pool.locals = newAccountSet(pool.signer)
for _, addr := range config.Locals {
log.Info("Setting new local account", "address", addr)
pool.locals.add(addr)
}
pool.priced = newTxPricedList(pool.all)
pool.reset(nil, chain.CurrentBlock().Header())
// If local transactions and journaling is enabled, load from disk
if !config.NoLocals && config.Journal != "" {
pool.journal = newTxJournal(config.Journal)
if err := pool.journal.load(pool.AddLocals); err != nil {
log.Warn("Failed to load transaction journal", "err", err)
}
if err := pool.journal.rotate(pool.local()); err != nil {
log.Warn("Failed to rotate transaction journal", "err", err)
}
}
// Subscribe events from blockchain
pool.blockConfirmedSub = pool.chain.SubscribeBlockConfirmedEvent(pool.blockConfirmedCh)
pool.chainHeadSub = pool.chain.SubscribeChainHeadEvent(pool.chainHeadCh)
// Start the event loop and return
pool.wg.Add(1)
go pool.loop()
return pool
}
// loop is the transaction pool's main event loop, waiting for and reacting to
// outside blockchain events as well as for various reporting and transaction
// eviction events.
func (pool *TxPool) loop() {
defer pool.wg.Done()
// Start the stats reporting and transaction eviction tickers
var prevPending, prevQueued, prevStales int
report := time.NewTicker(statsReportInterval)
defer report.Stop()
evict := time.NewTicker(evictionInterval)
defer evict.Stop()
journal := time.NewTicker(pool.config.Rejournal)
defer journal.Stop()
// Track the previous head headers for transaction reorgs
head := pool.chain.CurrentBlock()
// Keep waiting for and reacting to the various events
for {
select {
// Handle ChainHeadEvent
case ev := <-pool.chainHeadCh:
if pool.isBlockProposer {
break
}
if ev.Block != nil {
pool.mu.Lock()
if pool.chainconfig.IsHomestead(ev.Block.Number()) {
pool.homestead = true
}
pool.reset(head.Header(), ev.Block.Header())
head = ev.Block
pool.mu.Unlock()
}
// Be unsubscribed due to system stopped
case <-pool.chainHeadSub.Err():
return
// Handle BlockConfirmedEvent
case ev := <-pool.blockConfirmedCh:
if !pool.isBlockProposer {
break
}
if ev.Block != nil {
pool.mu.Lock()
if pool.chainconfig.IsHomestead(ev.Block.Number()) {
pool.homestead = true
}
pool.reset(head.Header(), ev.Block.Header())
head = ev.Block
pool.mu.Unlock()
}
// Be unsubscribed due to system stopped
case <-pool.blockConfirmedSub.Err():
return
// Handle stats reporting ticks
case <-report.C:
pool.mu.RLock()
pending, queued := pool.stats()
stales := pool.priced.stales
pool.mu.RUnlock()
if pending != prevPending || queued != prevQueued || stales != prevStales {
log.Debug("Transaction pool status report", "executable", pending, "queued", queued, "stales", stales)
prevPending, prevQueued, prevStales = pending, queued, stales
}
// Handle inactive account transaction eviction
case <-evict.C:
pool.mu.Lock()
for addr := range pool.queue {
// Skip local transactions from the eviction mechanism
if pool.locals.contains(addr) {
continue
}
// Any non-locals old enough should be removed
if time.Since(pool.beats[addr]) > pool.config.Lifetime {
for _, tx := range pool.queue[addr].Flatten() {
pool.removeTx(tx.Hash(), true)
}
}
}
pool.mu.Unlock()
// Handle local transaction journal rotation
case <-journal.C:
if pool.journal != nil {
pool.mu.Lock()
if err := pool.journal.rotate(pool.local()); err != nil {
log.Warn("Failed to rotate local tx journal", "err", err)
}
pool.mu.Unlock()
}
}
}
}
// lockedReset is a wrapper around reset to allow calling it in a thread safe
// manner. This method is only ever used in the tester!
func (pool *TxPool) lockedReset(oldHead, newHead *types.Header) {
pool.mu.Lock()
defer pool.mu.Unlock()
pool.reset(oldHead, newHead)
}
// reset retrieves the current state of the blockchain and ensures the content
// of the transaction pool is valid with regard to the chain state.
func (pool *TxPool) reset(oldHead, newHead *types.Header) {
// If we're reorging an old state, reinject all dropped transactions
var reinject types.Transactions
if oldHead != nil && oldHead.Hash() != newHead.ParentHash {
// If the reorg is too deep, avoid doing it (will happen during fast sync)
oldNum := oldHead.Number.Uint64()
newNum := newHead.Number.Uint64()
if depth := uint64(math.Abs(float64(oldNum) - float64(newNum))); depth > 64 {
log.Debug("Skipping deep transaction reorg", "depth", depth)
} else {
// Reorg seems shallow enough to pull in all transactions into memory
var discarded, included types.Transactions
var (
rem = pool.chain.GetBlock(oldHead.Hash(), oldHead.Number.Uint64())
add = pool.chain.GetBlock(newHead.Hash(), newHead.Number.Uint64())
)
for rem.NumberU64() > add.NumberU64() {
discarded = append(discarded, rem.Transactions()...)
if rem = pool.chain.GetBlock(rem.ParentHash(), rem.NumberU64()-1); rem == nil {
log.Error("Unrooted old chain seen by tx pool", "block", oldHead.Number, "hash", oldHead.Hash())
return
}
}
for add.NumberU64() > rem.NumberU64() {
included = append(included, add.Transactions()...)
if add = pool.chain.GetBlock(add.ParentHash(), add.NumberU64()-1); add == nil {
log.Error("Unrooted new chain seen by tx pool", "block", newHead.Number, "hash", newHead.Hash())
return
}
}
for rem.Hash() != add.Hash() {
discarded = append(discarded, rem.Transactions()...)
if rem = pool.chain.GetBlock(rem.ParentHash(), rem.NumberU64()-1); rem == nil {
log.Error("Unrooted old chain seen by tx pool", "block", oldHead.Number, "hash", oldHead.Hash())
return
}
included = append(included, add.Transactions()...)
if add = pool.chain.GetBlock(add.ParentHash(), add.NumberU64()-1); add == nil {
log.Error("Unrooted new chain seen by tx pool", "block", newHead.Number, "hash", newHead.Hash())
return
}
}
reinject = types.TxDifference(discarded, included)
}
}
// Initialize the internal state to the current head
if newHead == nil {
newHead = pool.chain.CurrentBlock().Header() // Special case during testing
}
statedb, err := pool.chain.StateAt(newHead.Root)
if err != nil {
log.Error("Failed to reset txpool state", "err", err)
return
}
pool.currentState = statedb
pool.pendingState = state.ManageState(statedb)
pool.currentMaxGas = newHead.GasLimit
// Inject any transactions discarded due to reorgs
log.Debug("Reinjecting stale transactions", "count", len(reinject))
senderCacher.recover(pool.signer, reinject)
pool.addTxsLocked(reinject, false)
// validate the pool of pending transactions, this will remove
// any transactions that have been included in the block or
// have been invalidated because of another transaction (e.g.
// higher gas price)
pool.demoteUnexecutables()
// Update all accounts to the latest known pending nonce
for addr, list := range pool.pending {
txs := list.Flatten() // Heavy but will be cached and is needed by the miner anyway
pool.pendingState.SetNonce(addr, txs[len(txs)-1].Nonce()+1)
}
// Check the queue and move transactions over to the pending if possible
// or remove those that have become invalid
pool.promoteExecutables(nil)
}
// Stop terminates the transaction pool.
func (pool *TxPool) Stop() {
// Unsubscribe all subscriptions registered from txpool
pool.scope.Close()
// Unsubscribe subscriptions registered from blockchain
pool.blockConfirmedSub.Unsubscribe()
pool.wg.Wait()
if pool.journal != nil {
pool.journal.close()
}
log.Info("Transaction pool stopped")
}
// SubscribeNewTxsEvent registers a subscription of NewTxsEvent and
// starts sending event to the given channel.
func (pool *TxPool) SubscribeNewTxsEvent(ch chan<- NewTxsEvent) event.Subscription {
return pool.scope.Track(pool.txFeed.Subscribe(ch))
}
// GasPrice returns the current gas price enforced by the transaction pool.
func (pool *TxPool) GasPrice() *big.Int {
pool.mu.RLock()
defer pool.mu.RUnlock()
return new(big.Int).Set(pool.gasPrice)
}
// SetGasPrice updates the minimum price required by the transaction pool for a
// new transaction, and drops all transactions below this threshold.
func (pool *TxPool) SetGasPrice(price *big.Int) {
pool.mu.Lock()
defer pool.mu.Unlock()
pool.gasPrice = price
for _, tx := range pool.priced.Cap(price, pool.locals) {
pool.removeTx(tx.Hash(), false)
}
log.Info("Transaction pool price threshold updated", "price", price)
}
// State returns the virtual managed state of the transaction pool.
func (pool *TxPool) State() *state.ManagedState {
pool.mu.RLock()
defer pool.mu.RUnlock()
return pool.pendingState
}
// Stats retrieves the current pool stats, namely the number of pending and the
// number of queued (non-executable) transactions.
func (pool *TxPool) Stats() (int, int) {
pool.mu.RLock()
defer pool.mu.RUnlock()
return pool.stats()
}
// stats retrieves the current pool stats, namely the number of pending and the
// number of queued (non-executable) transactions.
func (pool *TxPool) stats() (int, int) {
pending := 0
for _, list := range pool.pending {
pending += list.Len()
}
queued := 0
for _, list := range pool.queue {
queued += list.Len()
}
return pending, queued
}
// Content retrieves the data content of the transaction pool, returning all the
// pending as well as queued transactions, grouped by account and sorted by nonce.
func (pool *TxPool) Content() (map[common.Address]types.Transactions, map[common.Address]types.Transactions) {
pool.mu.Lock()
defer pool.mu.Unlock()
pending := make(map[common.Address]types.Transactions)
for addr, list := range pool.pending {
pending[addr] = list.Flatten()
}
queued := make(map[common.Address]types.Transactions)
for addr, list := range pool.queue {
queued[addr] = list.Flatten()
}
return pending, queued
}
// Pending retrieves all currently processable transactions, grouped by origin
// account and sorted by nonce. The returned transaction set is a copy and can be
// freely modified by calling code.
func (pool *TxPool) Pending() (map[common.Address]types.Transactions, error) {
pool.mu.Lock()
defer pool.mu.Unlock()
pending := make(map[common.Address]types.Transactions)
for addr, list := range pool.pending {
pending[addr] = list.Flatten()
}
return pending, nil
}
// Locals retrieves the accounts currently considered local by the pool.
func (pool *TxPool) Locals() []common.Address {
pool.mu.Lock()
defer pool.mu.Unlock()
return pool.locals.flatten()
}
// local retrieves all currently known local transactions, grouped by origin
// account and sorted by nonce. The returned transaction set is a copy and can be
// freely modified by calling code.
func (pool *TxPool) local() map[common.Address]types.Transactions {
txs := make(map[common.Address]types.Transactions)
for addr := range pool.locals.accounts {
if pending := pool.pending[addr]; pending != nil {
txs[addr] = append(txs[addr], pending.Flatten()...)
}
if queued := pool.queue[addr]; queued != nil {
txs[addr] = append(txs[addr], queued.Flatten()...)
}
}
return txs
}
// validateTx checks whether a transaction is valid according to the consensus
// rules and adheres to some heuristic limits of the local node (price and size).
func (pool *TxPool) validateTx(tx *types.Transaction, local bool) error {
// Heuristic limit, reject transactions over 32KB to prevent DOS attacks
if tx.Size() > 32*1024 {
return ErrOversizedData
}
// Transactions can't be negative. This may never happen using RLP decoded
// transactions but may occur if you create a transaction using the RPC.
if tx.Value().Sign() < 0 {
return ErrNegativeValue
}
// Ensure the transaction doesn't exceed the current block limit gas.
if pool.currentMaxGas < tx.Gas() {
return ErrGasLimit
}
// Make sure the transaction is signed properly
from, err := types.Sender(pool.signer, tx)
if err != nil {
return ErrInvalidSender
}
// Drop non-local transactions under our own minimal accepted gas price
local = local || pool.locals.contains(from) // account may be local even if the transaction arrived from the network
if !local && pool.gasPrice.Cmp(tx.GasPrice()) > 0 {
return ErrUnderpriced
}
// Ensure the transaction adheres to nonce ordering
if pool.currentState.GetNonce(from) > tx.Nonce() {
return ErrNonceTooLow
}
// Transactor should have enough funds to cover the costs
// cost == V + GP * GL
if pool.currentState.GetBalance(from).Cmp(tx.Cost()) < 0 {
return ErrInsufficientFunds
}
intrGas, err := IntrinsicGas(tx.Data(), tx.To() == nil, pool.homestead)
if err != nil {
return err
}
if tx.Gas() < intrGas {
return ErrIntrinsicGas
}
return nil
}
// add validates a transaction and inserts it into the non-executable queue for
// later pending promotion and execution. If the transaction is a replacement for
// an already pending or queued one, it overwrites the previous and returns this
// so outer code doesn't uselessly call promote.
//
// If a newly added transaction is marked as local, its sending account will be
// whitelisted, preventing any associated transaction from being dropped out of
// the pool due to pricing constraints.
func (pool *TxPool) add(tx *types.Transaction, local bool) (bool, error) {
// If the transaction is already known, discard it
hash := tx.Hash()
if pool.all.Get(hash) != nil {
log.Trace("Discarding already known transaction", "hash", hash)
return false, fmt.Errorf("known transaction: %x", hash)
}
// If the transaction fails basic validation, discard it
if err := pool.validateTx(tx, local); err != nil {
log.Trace("Discarding invalid transaction", "hash", hash, "err", err)
invalidTxCounter.Inc(1)
return false, err
}
// If the transaction pool is full, discard underpriced transactions
if uint64(pool.all.Count()) >= pool.config.GlobalSlots+pool.config.GlobalQueue {
// If the new transaction is underpriced, don't accept it
if !local && pool.priced.Underpriced(tx, pool.locals) {
log.Trace("Discarding underpriced transaction", "hash", hash, "price", tx.GasPrice())
underpricedTxCounter.Inc(1)
return false, ErrUnderpriced
}
// New transaction is better than our worse ones, make room for it
drop := pool.priced.Discard(pool.all.Count()-int(pool.config.GlobalSlots+pool.config.GlobalQueue-1), pool.locals)
for _, tx := range drop {
log.Trace("Discarding freshly underpriced transaction", "hash", tx.Hash(), "price", tx.GasPrice())
underpricedTxCounter.Inc(1)
pool.removeTx(tx.Hash(), false)
}
}
// If the transaction is replacing an already pending one, do directly
from, _ := types.Sender(pool.signer, tx) // already validated
if list := pool.pending[from]; list != nil && list.Overlaps(tx) {
// Nonce already pending, check if required price bump is met
inserted, old := list.Add(tx, pool.config.PriceBump)
if !inserted {
pendingDiscardCounter.Inc(1)
return false, ErrReplaceUnderpriced
}
// New transaction is better, replace old one
if old != nil {
pool.all.Remove(old.Hash())
pool.priced.Removed()
pendingReplaceCounter.Inc(1)
}
pool.all.Add(tx)
pool.priced.Put(tx)
pool.journalTx(from, tx)
log.Trace("Pooled new executable transaction", "hash", hash, "from", from, "to", tx.To())
// We've directly injected a replacement transaction, notify subsystems
go pool.txFeed.Send(NewTxsEvent{types.Transactions{tx}})
return old != nil, nil
}
// New transaction isn't replacing a pending one, push into queue
replace, err := pool.enqueueTx(hash, tx)
if err != nil {
return false, err
}
// Mark local addresses and journal local transactions
if local {
if !pool.locals.contains(from) {
log.Info("Setting new local account", "address", from)
pool.locals.add(from)
}
}
pool.journalTx(from, tx)
log.Trace("Pooled new future transaction", "hash", hash, "from", from, "to", tx.To())
return replace, nil
}
// enqueueTx inserts a new transaction into the non-executable transaction queue.
//
// Note, this method assumes the pool lock is held!
func (pool *TxPool) enqueueTx(hash common.Hash, tx *types.Transaction) (bool, error) {
// Try to insert the transaction into the future queue
from, _ := types.Sender(pool.signer, tx) // already validated
if pool.queue[from] == nil {
pool.queue[from] = newTxList(false)
}
inserted, old := pool.queue[from].Add(tx, pool.config.PriceBump)
if !inserted {
// An older transaction was better, discard this
queuedDiscardCounter.Inc(1)
return false, ErrReplaceUnderpriced
}
// Discard any previous transaction and mark this
if old != nil {
pool.all.Remove(old.Hash())
pool.priced.Removed()
queuedReplaceCounter.Inc(1)
}
if pool.all.Get(hash) == nil {
pool.all.Add(tx)
pool.priced.Put(tx)
}
return old != nil, nil
}
// journalTx adds the specified transaction to the local disk journal if it is
// deemed to have been sent from a local account.
func (pool *TxPool) journalTx(from common.Address, tx *types.Transaction) {
// Only journal if it's enabled and the transaction is local
if pool.journal == nil || !pool.locals.contains(from) {
return
}
if err := pool.journal.insert(tx); err != nil {
log.Warn("Failed to journal local transaction", "err", err)
}
}
// promoteTx adds a transaction to the pending (processable) list of transactions
// and returns whether it was inserted or an older was better.
//
// Note, this method assumes the pool lock is held!
func (pool *TxPool) promoteTx(addr common.Address, hash common.Hash, tx *types.Transaction) bool {
// Try to insert the transaction into the pending queue
if pool.pending[addr] == nil {
pool.pending[addr] = newTxList(true)
}
list := pool.pending[addr]
inserted, old := list.Add(tx, pool.config.PriceBump)
if !inserted {
// An older transaction was better, discard this
pool.all.Remove(hash)
pool.priced.Removed()
pendingDiscardCounter.Inc(1)
return false
}
// Otherwise discard any previous transaction and mark this
if old != nil {
pool.all.Remove(old.Hash())
pool.priced.Removed()
pendingReplaceCounter.Inc(1)
}
// Failsafe to work around direct pending inserts (tests)
if pool.all.Get(hash) == nil {
pool.all.Add(tx)
pool.priced.Put(tx)
}
// Set the potentially new pending nonce and notify any subsystems of the new tx
pool.beats[addr] = time.Now()
pool.pendingState.SetNonce(addr, tx.Nonce()+1)
return true
}
// AddLocal enqueues a single transaction into the pool if it is valid, marking
// the sender as a local one in the mean time, ensuring it goes around the local
// pricing constraints.
func (pool *TxPool) AddLocal(tx *types.Transaction) error {
return pool.addTx(tx, !pool.config.NoLocals)
}
// AddRemote enqueues a single transaction into the pool if it is valid. If the
// sender is not among the locally tracked ones, full pricing constraints will
// apply.
func (pool *TxPool) AddRemote(tx *types.Transaction) error {
return pool.addTx(tx, false)
}
// AddLocals enqueues a batch of transactions into the pool if they are valid,
// marking the senders as a local ones in the mean time, ensuring they go around
// the local pricing constraints.
func (pool *TxPool) AddLocals(txs []*types.Transaction) []error {
return pool.addTxs(txs, !pool.config.NoLocals)
}
// AddRemotes enqueues a batch of transactions into the pool if they are valid.
// If the senders are not among the locally tracked ones, full pricing constraints
// will apply.
func (pool *TxPool) AddRemotes(txs []*types.Transaction) []error {
return pool.addTxs(txs, false)
}
// addTx enqueues a single transaction into the pool if it is valid.
func (pool *TxPool) addTx(tx *types.Transaction, local bool) error {
pool.mu.Lock()
defer pool.mu.Unlock()
// Try to inject the transaction and update any state
replace, err := pool.add(tx, local)
if err != nil {
return err
}
// If we added a new transaction, run promotion checks and return
if !replace {
from, _ := types.Sender(pool.signer, tx) // already validated
pool.promoteExecutables([]common.Address{from})
}
return nil
}
// addTxs attempts to queue a batch of transactions if they are valid.
func (pool *TxPool) addTxs(txs []*types.Transaction, local bool) []error {
pool.mu.Lock()
defer pool.mu.Unlock()
return pool.addTxsLocked(txs, local)
}
// addTxsLocked attempts to queue a batch of transactions if they are valid,
// whilst assuming the transaction pool lock is already held.
func (pool *TxPool) addTxsLocked(txs []*types.Transaction, local bool) []error {
// Add the batch of transactions, tracking the accepted ones
dirty := make(map[common.Address]struct{})
errs := make([]error, len(txs))
for i, tx := range txs {
var replace bool
if replace, errs[i] = pool.add(tx, local); errs[i] == nil && !replace {
from, _ := types.Sender(pool.signer, tx) // already validated
dirty[from] = struct{}{}
}
}
// Only reprocess the internal state if something was actually added
if len(dirty) > 0 {
addrs := make([]common.Address, 0, len(dirty))
for addr := range dirty {
addrs = append(addrs, addr)
}
pool.promoteExecutables(addrs)
}
return errs
}
// Status returns the status (unknown/pending/queued) of a batch of transactions
// identified by their hashes.
func (pool *TxPool) Status(hashes []common.Hash) []TxStatus {
pool.mu.RLock()
defer pool.mu.RUnlock()
status := make([]TxStatus, len(hashes))
for i, hash := range hashes {
if tx := pool.all.Get(hash); tx != nil {
from, _ := types.Sender(pool.signer, tx) // already validated
if pool.pending[from] != nil && pool.pending[from].txs.items[tx.Nonce()] != nil {
status[i] = TxStatusPending
} else {
status[i] = TxStatusQueued
}
}
}
return status
}
// Get returns a transaction if it is contained in the pool
// and nil otherwise.
func (pool *TxPool) Get(hash common.Hash) *types.Transaction {
return pool.all.Get(hash)
}
// removeTx removes a single transaction from the queue, moving all subsequent
// transactions back to the future queue.
func (pool *TxPool) removeTx(hash common.Hash, outofbound bool) {
types.GlobalSigCache.Prune([]common.Hash{hash})
// Fetch the transaction we wish to delete
tx := pool.all.Get(hash)
if tx == nil {
return
}
addr, _ := types.Sender(pool.signer, tx) // already validated during insertion
// Remove it from the list of known transactions
pool.all.Remove(hash)
if outofbound {
pool.priced.Removed()
}
// Remove the transaction from the pending lists and reset the account nonce
if pending := pool.pending[addr]; pending != nil {
if removed, invalids := pending.Remove(tx); removed {
// If no more pending transactions are left, remove the list
if pending.Empty() {
delete(pool.pending, addr)
delete(pool.beats, addr)
}
// Postpone any invalidated transactions
for _, tx := range invalids {
pool.enqueueTx(tx.Hash(), tx)
}
// Update the account nonce if needed
if nonce := tx.Nonce(); pool.pendingState.GetNonce(addr) > nonce {
pool.pendingState.SetNonce(addr, nonce)
}
return
}
}
// Transaction is in the future queue
if future := pool.queue[addr]; future != nil {
future.Remove(tx)
if future.Empty() {
delete(pool.queue, addr)
}
}
}
// promoteExecutables moves transactions that have become processable from the
// future queue to the set of pending transactions. During this process, all
// invalidated transactions (low nonce, low balance) are deleted.
func (pool *TxPool) promoteExecutables(accounts []common.Address) {
// Track the promoted transactions to broadcast them at once
var promoted []*types.Transaction
// Gather all the accounts potentially needing updates
if accounts == nil {
accounts = make([]common.Address, 0, len(pool.queue))
for addr := range pool.queue {
accounts = append(accounts, addr)
}
}
// Iterate over all accounts and promote any executable transactions
for _, addr := range accounts {
list := pool.queue[addr]
if list == nil {
continue // Just in case someone calls with a non existing account
}
// Drop all transactions that are deemed too old (low nonce)
for _, tx := range list.Forward(pool.currentState.GetNonce(addr)) {
hash := tx.Hash()
log.Trace("Removed old queued transaction", "hash", hash)
pool.all.Remove(hash)
pool.priced.Removed()
}
// Drop all transactions that are too costly (low balance or out of gas)
drops, _ := list.Filter(pool.currentState.GetBalance(addr), pool.currentMaxGas)
for _, tx := range drops {
hash := tx.Hash()
log.Trace("Removed unpayable queued transaction", "hash", hash)
pool.all.Remove(hash)
pool.priced.Removed()
queuedNofundsCounter.Inc(1)
}
// Gather all executable transactions and promote them
for _, tx := range list.Ready(pool.pendingState.GetNonce(addr)) {
hash := tx.Hash()
if pool.promoteTx(addr, hash, tx) {
log.Trace("Promoting queued transaction", "hash", hash)
promoted = append(promoted, tx)
}
}
// Drop all transactions over the allowed limit
if !pool.locals.contains(addr) {
for _, tx := range list.Cap(int(pool.config.AccountQueue)) {
hash := tx.Hash()
pool.all.Remove(hash)
pool.priced.Removed()
queuedRateLimitCounter.Inc(1)
log.Trace("Removed cap-exceeding queued transaction", "hash", hash)
}
}
// Delete the entire queue entry if it became empty.
if list.Empty() {
delete(pool.queue, addr)
}
}
// Notify subsystem for new promoted transactions.
if len(promoted) > 0 {
go pool.txFeed.Send(NewTxsEvent{promoted})
}
// If the pending limit is overflown, start equalizing allowances
pending := uint64(0)
for _, list := range pool.pending {
pending += uint64(list.Len())
}
if pending > pool.config.GlobalSlots {
pendingBeforeCap := pending
// Assemble a spam order to penalize large transactors first
spammers := prque.New(nil)
for addr, list := range pool.pending {
// Only evict transactions from high rollers
if !pool.locals.contains(addr) && uint64(list.Len()) > pool.config.AccountSlots {
spammers.Push(addr, int64(list.Len()))
}
}
// Gradually drop transactions from offenders
offenders := []common.Address{}
for pending > pool.config.GlobalSlots && !spammers.Empty() {
// Retrieve the next offender if not local address
offender, _ := spammers.Pop()
offenders = append(offenders, offender.(common.Address))
// Equalize balances until all the same or below threshold
if len(offenders) > 1 {
// Calculate the equalization threshold for all current offenders
threshold := pool.pending[offender.(common.Address)].Len()
// Iteratively reduce all offenders until below limit or threshold reached
for pending > pool.config.GlobalSlots && pool.pending[offenders[len(offenders)-2]].Len() > threshold {
for i := 0; i < len(offenders)-1; i++ {
list := pool.pending[offenders[i]]
for _, tx := range list.Cap(list.Len() - 1) {
// Drop the transaction from the global pools too
hash := tx.Hash()
pool.all.Remove(hash)
pool.priced.Removed()
// Update the account nonce to the dropped transaction
if nonce := tx.Nonce(); pool.pendingState.GetNonce(offenders[i]) > nonce {
pool.pendingState.SetNonce(offenders[i], nonce)
}
log.Trace("Removed fairness-exceeding pending transaction", "hash", hash)
}
pending--
}
}
}
}
// If still above threshold, reduce to limit or min allowance
if pending > pool.config.GlobalSlots && len(offenders) > 0 {
for pending > pool.config.GlobalSlots && uint64(pool.pending[offenders[len(offenders)-1]].Len()) > pool.config.AccountSlots {
for _, addr := range offenders {
list := pool.pending[addr]
for _, tx := range list.Cap(list.Len() - 1) {
// Drop the transaction from the global pools too
hash := tx.Hash()
pool.all.Remove(hash)
pool.priced.Removed()
// Update the account nonce to the dropped transaction
if nonce := tx.Nonce(); pool.pendingState.GetNonce(addr) > nonce {
pool.pendingState.SetNonce(addr, nonce)
}
log.Trace("Removed fairness-exceeding pending transaction", "hash", hash)
}
pending--
}
}
}
pendingRateLimitCounter.Inc(int64(pendingBeforeCap - pending))
}
// If we've queued more transactions than the hard limit, drop oldest ones
queued := uint64(0)
for _, list := range pool.queue {
queued += uint64(list.Len())
}
if queued > pool.config.GlobalQueue {
// Sort all accounts with queued transactions by heartbeat
addresses := make(addressesByHeartbeat, 0, len(pool.queue))
for addr := range pool.queue {
if !pool.locals.contains(addr) { // don't drop locals
addresses = append(addresses, addressByHeartbeat{addr, pool.beats[addr]})
}
}
sort.Sort(addresses)
// Drop transactions until the total is below the limit or only locals remain
for drop := queued - pool.config.GlobalQueue; drop > 0 && len(addresses) > 0; {
addr := addresses[len(addresses)-1]
list := pool.queue[addr.address]
addresses = addresses[:len(addresses)-1]
// Drop all transactions if they are less than the overflow
if size := uint64(list.Len()); size <= drop {
for _, tx := range list.Flatten() {
pool.removeTx(tx.Hash(), true)
}
drop -= size
queuedRateLimitCounter.Inc(int64(size))
continue
}
// Otherwise drop only last few transactions
txs := list.Flatten()
for i := len(txs) - 1; i >= 0 && drop > 0; i-- {
pool.removeTx(txs[i].Hash(), true)
drop--
queuedRateLimitCounter.Inc(1)
}
}
}
}
// demoteUnexecutables removes invalid and processed transactions from the pools
// executable/pending queue and any subsequent transactions that become unexecutable
// are moved back into the future queue.
func (pool *TxPool) demoteUnexecutables() {
// Iterate over all accounts and demote any non-executable transactions
for addr, list := range pool.pending {
nonce := pool.currentState.GetNonce(addr)
// Drop all transactions that are deemed too old (low nonce)
for _, tx := range list.Forward(nonce) {
hash := tx.Hash()
log.Trace("Removed old pending transaction", "hash", hash)
pool.all.Remove(hash)
pool.priced.Removed()
}
// Drop all transactions that are too costly (low balance or out of gas), and queue any invalids back for later
drops, invalids := list.Filter(pool.currentState.GetBalance(addr), pool.currentMaxGas)
for _, tx := range drops {
hash := tx.Hash()
log.Trace("Removed unpayable pending transaction", "hash", hash)
pool.all.Remove(hash)
pool.priced.Removed()
pendingNofundsCounter.Inc(1)
}
for _, tx := range invalids {
hash := tx.Hash()
log.Trace("Demoting pending transaction", "hash", hash)
pool.enqueueTx(hash, tx)
}
// If there's a gap in front, alert (should never happen) and postpone all transactions
if list.Len() > 0 && list.txs.Get(nonce) == nil {
for _, tx := range list.Cap(0) {
hash := tx.Hash()
log.Error("Demoting invalidated transaction", "hash", hash)
pool.enqueueTx(hash, tx)
}
}
// Delete the entire queue entry if it became empty.
if list.Empty() {
delete(pool.pending, addr)
delete(pool.beats, addr)
}
}
}
// addressByHeartbeat is an account address tagged with its last activity timestamp.
type addressByHeartbeat struct {
address common.Address
heartbeat time.Time
}
type addressesByHeartbeat []addressByHeartbeat
func (a addressesByHeartbeat) Len() int { return len(a) }
func (a addressesByHeartbeat) Less(i, j int) bool { return a[i].heartbeat.Before(a[j].heartbeat) }
func (a addressesByHeartbeat) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
// accountSet is simply a set of addresses to check for existence, and a signer
// capable of deriving addresses from transactions.
type accountSet struct {
accounts map[common.Address]struct{}
signer types.Signer
cache *[]common.Address
}
// newAccountSet creates a new address set with an associated signer for sender
// derivations.
func newAccountSet(signer types.Signer) *accountSet {
return &accountSet{
accounts: make(map[common.Address]struct{}),
signer: signer,
}
}
// contains checks if a given address is contained within the set.
func (as *accountSet) contains(addr common.Address) bool {
_, exist := as.accounts[addr]
return exist
}
// containsTx checks if the sender of a given tx is within the set. If the sender
// cannot be derived, this method returns false.
func (as *accountSet) containsTx(tx *types.Transaction) bool {
if addr, err := types.Sender(as.signer, tx); err == nil {
return as.contains(addr)
}
return false
}
// add inserts a new address into the set to track.
func (as *accountSet) add(addr common.Address) {
as.accounts[addr] = struct{}{}
as.cache = nil
}
// flatten returns the list of addresses within this set, also caching it for later
// reuse. The returned slice should not be changed!
func (as *accountSet) flatten() []common.Address {
if as.cache == nil {
accounts := make([]common.Address, 0, len(as.accounts))
for account := range as.accounts {
accounts = append(accounts, account)
}
as.cache = &accounts
}
return *as.cache
}
// txLookup is used internally by TxPool to track transactions while allowing lookup without
// mutex contention.
//
// Note, although this type is properly protected against concurrent access, it
// is **not** a type that should ever be mutated or even exposed outside of the
// transaction pool, since its internal state is tightly coupled with the pools
// internal mechanisms. The sole purpose of the type is to permit out-of-bound
// peeking into the pool in TxPool.Get without having to acquire the widely scoped
// TxPool.mu mutex.
type txLookup struct {
all map[common.Hash]*types.Transaction
lock sync.RWMutex
}
// newTxLookup returns a new txLookup structure.
func newTxLookup() *txLookup {
return &txLookup{
all: make(map[common.Hash]*types.Transaction),
}
}
// Range calls f on each key and value present in the map.
func (t *txLookup) Range(f func(hash common.Hash, tx *types.Transaction) bool) {
t.lock.RLock()
defer t.lock.RUnlock()
for key, value := range t.all {
if !f(key, value) {
break
}
}
}
// Get returns a transaction if it exists in the lookup, or nil if not found.
func (t *txLookup) Get(hash common.Hash) *types.Transaction {
t.lock.RLock()
defer t.lock.RUnlock()
return t.all[hash]
}
// Count returns the current number of items in the lookup.
func (t *txLookup) Count() int {
t.lock.RLock()
defer t.lock.RUnlock()
return len(t.all)
}
// Add adds a transaction to the lookup.
func (t *txLookup) Add(tx *types.Transaction) {
t.lock.Lock()
defer t.lock.Unlock()
t.all[tx.Hash()] = tx
}
// Remove removes a transaction from the lookup.
func (t *txLookup) Remove(hash common.Hash) {
t.lock.Lock()
defer t.lock.Unlock()
delete(t.all, hash)
}