neoneo-go/pkg/core/mem_pool.go
Roman Khimov 5d68f88196 core: fix and speed up mempool Verify()
First of all, it was wrong, it was not checking for inputs really, it compared
tx hashes for some reason, second, when it did compare inputs it compared only
the PrevIndex part of them which is also wrong.

Also, there is absolutely no reason to go through GetVerifiedTransactions()
here, we don't need this copy of pointers and it can also be outdated by the
time we're to finish our check.

Before:
BenchmarkTXPerformanceTest-4
    5000            485506 ns/op           65886 B/op        409 allocs/op
ok      github.com/CityOfZion/neo-go/integration        3.212s

After:
enchmarkTXPerformanceTest-4
    5000            371104 ns/op           44367 B/op        408 allocs/op
ok      github.com/CityOfZion/neo-go/integration        2.712s
2019-12-13 23:23:33 +03:00

303 lines
8.9 KiB
Go

package core
import (
"sort"
"sync"
"time"
"github.com/CityOfZion/neo-go/pkg/core/transaction"
"github.com/CityOfZion/neo-go/pkg/util"
)
// PoolItem represents a transaction in the the Memory pool.
type PoolItem struct {
txn *transaction.Transaction
timeStamp time.Time
fee Feer
}
// PoolItems slice of PoolItem.
type PoolItems []*PoolItem
// MemPool stores the unconfirms transactions.
type MemPool struct {
lock *sync.RWMutex
unsortedTxn map[util.Uint256]*PoolItem
unverifiedTxn map[util.Uint256]*PoolItem
sortedHighPrioTxn PoolItems
sortedLowPrioTxn PoolItems
unverifiedSortedHighPrioTxn PoolItems
unverifiedSortedLowPrioTxn PoolItems
capacity int
}
func (p PoolItems) Len() int { return len(p) }
func (p PoolItems) Swap(i, j int) { p[i], p[j] = p[j], p[i] }
func (p PoolItems) Less(i, j int) bool { return p[i].CompareTo(p[j]) < 0 }
// CompareTo returns the difference between two PoolItems.
// difference < 0 implies p < otherP.
// difference = 0 implies p = otherP.
// difference > 0 implies p > otherP.
func (p PoolItem) CompareTo(otherP *PoolItem) int {
if otherP == nil {
return 1
}
if p.fee.IsLowPriority(p.txn) && p.fee.IsLowPriority(otherP.txn) {
thisIsClaimTx := p.txn.Type == transaction.ClaimType
otherIsClaimTx := otherP.txn.Type == transaction.ClaimType
if thisIsClaimTx != otherIsClaimTx {
// This is a claim Tx and other isn't.
if thisIsClaimTx {
return 1
}
// The other is claim Tx and this isn't.
return -1
}
}
// Fees sorted ascending.
pFPB := p.fee.FeePerByte(p.txn)
otherFPB := p.fee.FeePerByte(otherP.txn)
if ret := pFPB.CompareTo(otherFPB); ret != 0 {
return ret
}
pNF := p.fee.NetworkFee(p.txn)
otherNF := p.fee.NetworkFee(otherP.txn)
if ret := pNF.CompareTo(otherNF); ret != 0 {
return ret
}
// Transaction hash sorted descending.
return otherP.txn.Hash().CompareTo(p.txn.Hash())
}
// Count returns the total number of uncofirm transactions.
func (mp MemPool) Count() int {
mp.lock.RLock()
defer mp.lock.RUnlock()
return len(mp.unsortedTxn) + len(mp.unverifiedTxn)
}
// ContainsKey checks if a transactions hash is in the MemPool.
func (mp MemPool) ContainsKey(hash util.Uint256) bool {
mp.lock.RLock()
defer mp.lock.RUnlock()
if _, ok := mp.unsortedTxn[hash]; ok {
return true
}
if _, ok := mp.unverifiedTxn[hash]; ok {
return true
}
return false
}
// TryAdd try to add the PoolItem to the MemPool.
func (mp MemPool) TryAdd(hash util.Uint256, pItem *PoolItem) bool {
var pool PoolItems
mp.lock.Lock()
if _, ok := mp.unsortedTxn[hash]; ok {
mp.lock.Unlock()
return false
}
mp.unsortedTxn[hash] = pItem
mp.lock.Unlock()
if pItem.fee.IsLowPriority(pItem.txn) {
pool = mp.sortedLowPrioTxn
} else {
pool = mp.sortedHighPrioTxn
}
mp.lock.Lock()
pool = append(pool, pItem)
sort.Sort(pool)
mp.lock.Unlock()
if mp.Count() > mp.capacity {
(&mp).RemoveOverCapacity()
}
mp.lock.RLock()
_, ok := mp.unsortedTxn[hash]
updateMempoolMetrics(len(mp.unsortedTxn), len(mp.unverifiedTxn))
mp.lock.RUnlock()
return ok
}
// Remove removes an item from the mempool, if it exists there (and does
// nothing if it doesn't).
func (mp *MemPool) Remove(hash util.Uint256) {
var mapAndPools = []struct {
unsortedMap map[util.Uint256]*PoolItem
sortedPools []*PoolItems
}{
{unsortedMap: mp.unsortedTxn, sortedPools: []*PoolItems{&mp.sortedHighPrioTxn, &mp.sortedLowPrioTxn}},
{unsortedMap: mp.unverifiedTxn, sortedPools: []*PoolItems{&mp.unverifiedSortedHighPrioTxn, &mp.unverifiedSortedLowPrioTxn}},
}
mp.lock.Lock()
for _, mapAndPool := range mapAndPools {
if _, ok := mapAndPool.unsortedMap[hash]; ok {
delete(mapAndPool.unsortedMap, hash)
for _, pool := range mapAndPool.sortedPools {
var num int
var item *PoolItem
for num, item = range *pool {
if hash.Equals(item.txn.Hash()) {
break
}
}
if num < len(*pool)-1 {
*pool = append((*pool)[:num], (*pool)[num+1:]...)
} else if num == len(*pool)-1 {
*pool = (*pool)[:num]
}
}
}
}
updateMempoolMetrics(len(mp.unsortedTxn), len(mp.unverifiedTxn))
mp.lock.Unlock()
}
// RemoveOverCapacity removes transactions with lowest fees until the total number of transactions
// in the MemPool is within the capacity of the MemPool.
func (mp *MemPool) RemoveOverCapacity() {
for mp.Count()-mp.capacity > 0 {
mp.lock.Lock()
if minItem, argPosition := getLowestFeeTransaction(mp.sortedLowPrioTxn, mp.unverifiedSortedLowPrioTxn); minItem != nil {
if argPosition == 1 {
// minItem belongs to the mp.sortedLowPrioTxn slice.
// The corresponding unsorted pool is is mp.unsortedTxn.
delete(mp.unsortedTxn, minItem.txn.Hash())
mp.sortedLowPrioTxn = append(mp.sortedLowPrioTxn[:0], mp.sortedLowPrioTxn[1:]...)
} else {
// minItem belongs to the mp.unverifiedSortedLowPrioTxn slice.
// The corresponding unsorted pool is is mp.unverifiedTxn.
delete(mp.unverifiedTxn, minItem.txn.Hash())
mp.unverifiedSortedLowPrioTxn = append(mp.unverifiedSortedLowPrioTxn[:0], mp.unverifiedSortedLowPrioTxn[1:]...)
}
} else if minItem, argPosition := getLowestFeeTransaction(mp.sortedHighPrioTxn, mp.unverifiedSortedHighPrioTxn); minItem != nil {
if argPosition == 1 {
// minItem belongs to the mp.sortedHighPrioTxn slice.
// The corresponding unsorted pool is is mp.unsortedTxn.
delete(mp.unsortedTxn, minItem.txn.Hash())
mp.sortedHighPrioTxn = append(mp.sortedHighPrioTxn[:0], mp.sortedHighPrioTxn[1:]...)
} else {
// minItem belongs to the mp.unverifiedSortedHighPrioTxn slice.
// The corresponding unsorted pool is is mp.unverifiedTxn.
delete(mp.unverifiedTxn, minItem.txn.Hash())
mp.unverifiedSortedHighPrioTxn = append(mp.unverifiedSortedHighPrioTxn[:0], mp.unverifiedSortedHighPrioTxn[1:]...)
}
}
updateMempoolMetrics(len(mp.unsortedTxn), len(mp.unverifiedTxn))
mp.lock.Unlock()
}
}
// NewPoolItem returns a new PoolItem.
func NewPoolItem(t *transaction.Transaction, fee Feer) *PoolItem {
return &PoolItem{
txn: t,
timeStamp: time.Now().UTC(),
fee: fee,
}
}
// NewMemPool returns a new MemPool struct.
func NewMemPool(capacity int) MemPool {
return MemPool{
lock: new(sync.RWMutex),
unsortedTxn: make(map[util.Uint256]*PoolItem),
unverifiedTxn: make(map[util.Uint256]*PoolItem),
capacity: capacity,
}
}
// TryGetValue returns a transaction if it exists in the memory pool.
func (mp MemPool) TryGetValue(hash util.Uint256) (*transaction.Transaction, bool) {
mp.lock.RLock()
defer mp.lock.RUnlock()
if pItem, ok := mp.unsortedTxn[hash]; ok {
return pItem.txn, ok
}
if pItem, ok := mp.unverifiedTxn[hash]; ok {
return pItem.txn, ok
}
return nil, false
}
// getLowestFeeTransaction returns the PoolItem with the lowest fee amongst the "verifiedTxnSorted"
// and "unverifiedTxnSorted" PoolItems along with a integer. The integer can assume two values, 1 and 2 which indicate
// that the PoolItem with the lowest fee was found in "verifiedTxnSorted" respectively in "unverifiedTxnSorted".
// "verifiedTxnSorted" and "unverifiedTxnSorted" are sorted slice order by transaction fee ascending. This means that
// the transaction with lowest fee start at index 0.
// Reference: GetLowestFeeTransaction method in C# (https://github.com/neo-project/neo/blob/master/neo/Ledger/MemoryPool.cs)
func getLowestFeeTransaction(verifiedTxnSorted PoolItems, unverifiedTxnSorted PoolItems) (*PoolItem, int) {
minItem := min(unverifiedTxnSorted)
verifiedMin := min(verifiedTxnSorted)
if verifiedMin == nil || (minItem != nil && verifiedMin.CompareTo(minItem) >= 0) {
return minItem, 2
}
minItem = verifiedMin
return minItem, 1
}
// min returns the minimum item in a ascending sorted slice of pool items.
// The function can't be applied to unsorted slice!
func min(sortedPool PoolItems) *PoolItem {
if len(sortedPool) == 0 {
return nil
}
return sortedPool[0]
}
// GetVerifiedTransactions returns a slice of Input from all the transactions in the memory pool
// whose hash is not included in excludedHashes.
func (mp *MemPool) GetVerifiedTransactions() []*transaction.Transaction {
mp.lock.RLock()
defer mp.lock.RUnlock()
var t = make([]*transaction.Transaction, len(mp.unsortedTxn))
var i int
for _, p := range mp.unsortedTxn {
t[i] = p.txn
i++
}
return t
}
// Verify verifies if the inputs of a transaction tx are already used in any other transaction in the memory pool.
// If yes, the transaction tx is not a valid transaction and the function return false.
// If no, the transaction tx is a valid transaction and the function return true.
func (mp MemPool) Verify(tx *transaction.Transaction) bool {
mp.lock.RLock()
defer mp.lock.RUnlock()
for _, item := range mp.unsortedTxn {
for i := range item.txn.Inputs {
for j := 0; j < len(tx.Inputs); j++ {
if item.txn.Inputs[i] == tx.Inputs[j] {
return false
}
}
}
}
return true
}