bsc/core/tx_cacher.go
2018-08-13 11:40:52 +03:00

106 lines
3.5 KiB
Go

// Copyright 2018 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 (
"runtime"
"github.com/ethereum/go-ethereum/core/types"
)
// senderCacher is a concurrent transaction sender recoverer anc cacher.
var senderCacher = newTxSenderCacher(runtime.NumCPU())
// txSenderCacherRequest is a request for recovering transaction senders with a
// specific signature scheme and caching it into the transactions themselves.
//
// The inc field defines the number of transactions to skip after each recovery,
// which is used to feed the same underlying input array to different threads but
// ensure they process the early transactions fast.
type txSenderCacherRequest struct {
signer types.Signer
txs []*types.Transaction
inc int
}
// txSenderCacher is a helper structure to concurrently ecrecover transaction
// senders from digital signatures on background threads.
type txSenderCacher struct {
threads int
tasks chan *txSenderCacherRequest
}
// newTxSenderCacher creates a new transaction sender background cacher and starts
// as many processing goroutines as allowed by the GOMAXPROCS on construction.
func newTxSenderCacher(threads int) *txSenderCacher {
cacher := &txSenderCacher{
tasks: make(chan *txSenderCacherRequest, threads),
threads: threads,
}
for i := 0; i < threads; i++ {
go cacher.cache()
}
return cacher
}
// cache is an infinite loop, caching transaction senders from various forms of
// data structures.
func (cacher *txSenderCacher) cache() {
for task := range cacher.tasks {
for i := 0; i < len(task.txs); i += task.inc {
types.Sender(task.signer, task.txs[i])
}
}
}
// recover recovers the senders from a batch of transactions and caches them
// back into the same data structures. There is no validation being done, nor
// any reaction to invalid signatures. That is up to calling code later.
func (cacher *txSenderCacher) recover(signer types.Signer, txs []*types.Transaction) {
// If there's nothing to recover, abort
if len(txs) == 0 {
return
}
// Ensure we have meaningful task sizes and schedule the recoveries
tasks := cacher.threads
if len(txs) < tasks*4 {
tasks = (len(txs) + 3) / 4
}
for i := 0; i < tasks; i++ {
cacher.tasks <- &txSenderCacherRequest{
signer: signer,
txs: txs[i:],
inc: tasks,
}
}
}
// recoverFromBlocks recovers the senders from a batch of blocks and caches them
// back into the same data structures. There is no validation being done, nor
// any reaction to invalid signatures. That is up to calling code later.
func (cacher *txSenderCacher) recoverFromBlocks(signer types.Signer, blocks []*types.Block) {
count := 0
for _, block := range blocks {
count += len(block.Transactions())
}
txs := make([]*types.Transaction, 0, count)
for _, block := range blocks {
txs = append(txs, block.Transactions()...)
}
cacher.recover(signer, txs)
}