go-pulse/les/benchmark.go

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les, les/flowcontrol: improved request serving and flow control (#18230) This change - implements concurrent LES request serving even for a single peer. - replaces the request cost estimation method with a cost table based on benchmarks which gives much more consistent results. Until now the allowed number of light peers was just a guess which probably contributed a lot to the fluctuating quality of available service. Everything related to request cost is implemented in a single object, the 'cost tracker'. It uses a fixed cost table with a global 'correction factor'. Benchmark code is included and can be run at any time to adapt costs to low-level implementation changes. - reimplements flowcontrol.ClientManager in a cleaner and more efficient way, with added capabilities: There is now control over bandwidth, which allows using the flow control parameters for client prioritization. Target utilization over 100 percent is now supported to model concurrent request processing. Total serving bandwidth is reduced during block processing to prevent database contention. - implements an RPC API for the LES servers allowing server operators to assign priority bandwidth to certain clients and change prioritized status even while the client is connected. The new API is meant for cases where server operators charge for LES using an off-protocol mechanism. - adds a unit test for the new client manager. - adds an end-to-end test using the network simulator that tests bandwidth control functions through the new API.
2019-02-26 11:32:48 +00:00
// 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 les
import (
"encoding/binary"
"fmt"
"math/big"
"math/rand"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/common/mclock"
"github.com/ethereum/go-ethereum/core/rawdb"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/les/flowcontrol"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/p2p"
"github.com/ethereum/go-ethereum/p2p/enode"
"github.com/ethereum/go-ethereum/params"
"github.com/ethereum/go-ethereum/rlp"
)
// requestBenchmark is an interface for different randomized request generators
type requestBenchmark interface {
// init initializes the generator for generating the given number of randomized requests
init(pm *ProtocolManager, count int) error
// request initiates sending a single request to the given peer
request(peer *peer, index int) error
}
// benchmarkBlockHeaders implements requestBenchmark
type benchmarkBlockHeaders struct {
amount, skip int
reverse, byHash bool
offset, randMax int64
hashes []common.Hash
}
func (b *benchmarkBlockHeaders) init(pm *ProtocolManager, count int) error {
d := int64(b.amount-1) * int64(b.skip+1)
b.offset = 0
b.randMax = pm.blockchain.CurrentHeader().Number.Int64() + 1 - d
if b.randMax < 0 {
return fmt.Errorf("chain is too short")
}
if b.reverse {
b.offset = d
}
if b.byHash {
b.hashes = make([]common.Hash, count)
for i := range b.hashes {
b.hashes[i] = rawdb.ReadCanonicalHash(pm.chainDb, uint64(b.offset+rand.Int63n(b.randMax)))
}
}
return nil
}
func (b *benchmarkBlockHeaders) request(peer *peer, index int) error {
if b.byHash {
return peer.RequestHeadersByHash(0, 0, b.hashes[index], b.amount, b.skip, b.reverse)
} else {
return peer.RequestHeadersByNumber(0, 0, uint64(b.offset+rand.Int63n(b.randMax)), b.amount, b.skip, b.reverse)
}
}
// benchmarkBodiesOrReceipts implements requestBenchmark
type benchmarkBodiesOrReceipts struct {
receipts bool
hashes []common.Hash
}
func (b *benchmarkBodiesOrReceipts) init(pm *ProtocolManager, count int) error {
randMax := pm.blockchain.CurrentHeader().Number.Int64() + 1
b.hashes = make([]common.Hash, count)
for i := range b.hashes {
b.hashes[i] = rawdb.ReadCanonicalHash(pm.chainDb, uint64(rand.Int63n(randMax)))
}
return nil
}
func (b *benchmarkBodiesOrReceipts) request(peer *peer, index int) error {
if b.receipts {
return peer.RequestReceipts(0, 0, []common.Hash{b.hashes[index]})
} else {
return peer.RequestBodies(0, 0, []common.Hash{b.hashes[index]})
}
}
// benchmarkProofsOrCode implements requestBenchmark
type benchmarkProofsOrCode struct {
code bool
headHash common.Hash
}
func (b *benchmarkProofsOrCode) init(pm *ProtocolManager, count int) error {
b.headHash = pm.blockchain.CurrentHeader().Hash()
return nil
}
func (b *benchmarkProofsOrCode) request(peer *peer, index int) error {
key := make([]byte, 32)
rand.Read(key)
if b.code {
return peer.RequestCode(0, 0, []CodeReq{{BHash: b.headHash, AccKey: key}})
} else {
return peer.RequestProofs(0, 0, []ProofReq{{BHash: b.headHash, Key: key}})
}
}
// benchmarkHelperTrie implements requestBenchmark
type benchmarkHelperTrie struct {
bloom bool
reqCount int
sectionCount, headNum uint64
}
func (b *benchmarkHelperTrie) init(pm *ProtocolManager, count int) error {
if b.bloom {
b.sectionCount, b.headNum, _ = pm.server.bloomTrieIndexer.Sections()
} else {
b.sectionCount, _, _ = pm.server.chtIndexer.Sections()
b.headNum = b.sectionCount*params.CHTFrequency - 1
les, les/flowcontrol: improved request serving and flow control (#18230) This change - implements concurrent LES request serving even for a single peer. - replaces the request cost estimation method with a cost table based on benchmarks which gives much more consistent results. Until now the allowed number of light peers was just a guess which probably contributed a lot to the fluctuating quality of available service. Everything related to request cost is implemented in a single object, the 'cost tracker'. It uses a fixed cost table with a global 'correction factor'. Benchmark code is included and can be run at any time to adapt costs to low-level implementation changes. - reimplements flowcontrol.ClientManager in a cleaner and more efficient way, with added capabilities: There is now control over bandwidth, which allows using the flow control parameters for client prioritization. Target utilization over 100 percent is now supported to model concurrent request processing. Total serving bandwidth is reduced during block processing to prevent database contention. - implements an RPC API for the LES servers allowing server operators to assign priority bandwidth to certain clients and change prioritized status even while the client is connected. The new API is meant for cases where server operators charge for LES using an off-protocol mechanism. - adds a unit test for the new client manager. - adds an end-to-end test using the network simulator that tests bandwidth control functions through the new API.
2019-02-26 11:32:48 +00:00
}
if b.sectionCount == 0 {
return fmt.Errorf("no processed sections available")
}
return nil
}
func (b *benchmarkHelperTrie) request(peer *peer, index int) error {
reqs := make([]HelperTrieReq, b.reqCount)
if b.bloom {
bitIdx := uint16(rand.Intn(2048))
for i := range reqs {
key := make([]byte, 10)
binary.BigEndian.PutUint16(key[:2], bitIdx)
binary.BigEndian.PutUint64(key[2:], uint64(rand.Int63n(int64(b.sectionCount))))
reqs[i] = HelperTrieReq{Type: htBloomBits, TrieIdx: b.sectionCount - 1, Key: key}
}
} else {
for i := range reqs {
key := make([]byte, 8)
binary.BigEndian.PutUint64(key[:], uint64(rand.Int63n(int64(b.headNum))))
reqs[i] = HelperTrieReq{Type: htCanonical, TrieIdx: b.sectionCount - 1, Key: key, AuxReq: auxHeader}
}
}
return peer.RequestHelperTrieProofs(0, 0, reqs)
}
// benchmarkTxSend implements requestBenchmark
type benchmarkTxSend struct {
txs types.Transactions
}
func (b *benchmarkTxSend) init(pm *ProtocolManager, count int) error {
key, _ := crypto.GenerateKey()
addr := crypto.PubkeyToAddress(key.PublicKey)
signer := types.NewEIP155Signer(big.NewInt(18))
b.txs = make(types.Transactions, count)
for i := range b.txs {
data := make([]byte, txSizeCostLimit)
rand.Read(data)
tx, err := types.SignTx(types.NewTransaction(0, addr, new(big.Int), 0, new(big.Int), data), signer, key)
if err != nil {
panic(err)
}
b.txs[i] = tx
}
return nil
}
func (b *benchmarkTxSend) request(peer *peer, index int) error {
enc, _ := rlp.EncodeToBytes(types.Transactions{b.txs[index]})
return peer.SendTxs(0, 0, enc)
}
// benchmarkTxStatus implements requestBenchmark
type benchmarkTxStatus struct{}
func (b *benchmarkTxStatus) init(pm *ProtocolManager, count int) error {
return nil
}
func (b *benchmarkTxStatus) request(peer *peer, index int) error {
var hash common.Hash
rand.Read(hash[:])
return peer.RequestTxStatus(0, 0, []common.Hash{hash})
}
// benchmarkSetup stores measurement data for a single benchmark type
type benchmarkSetup struct {
req requestBenchmark
totalCount int
totalTime, avgTime time.Duration
maxInSize, maxOutSize uint32
err error
}
// runBenchmark runs a benchmark cycle for all benchmark types in the specified
// number of passes
func (pm *ProtocolManager) runBenchmark(benchmarks []requestBenchmark, passCount int, targetTime time.Duration) []*benchmarkSetup {
setup := make([]*benchmarkSetup, len(benchmarks))
for i, b := range benchmarks {
setup[i] = &benchmarkSetup{req: b}
}
for i := 0; i < passCount; i++ {
log.Info("Running benchmark", "pass", i+1, "total", passCount)
todo := make([]*benchmarkSetup, len(benchmarks))
copy(todo, setup)
for len(todo) > 0 {
// select a random element
index := rand.Intn(len(todo))
next := todo[index]
todo[index] = todo[len(todo)-1]
todo = todo[:len(todo)-1]
if next.err == nil {
// calculate request count
count := 50
if next.totalTime > 0 {
count = int(uint64(next.totalCount) * uint64(targetTime) / uint64(next.totalTime))
}
if err := pm.measure(next, count); err != nil {
next.err = err
}
}
}
}
log.Info("Benchmark completed")
for _, s := range setup {
if s.err == nil {
s.avgTime = s.totalTime / time.Duration(s.totalCount)
}
}
return setup
}
// meteredPipe implements p2p.MsgReadWriter and remembers the largest single
// message size sent through the pipe
type meteredPipe struct {
rw p2p.MsgReadWriter
maxSize uint32
}
func (m *meteredPipe) ReadMsg() (p2p.Msg, error) {
return m.rw.ReadMsg()
}
func (m *meteredPipe) WriteMsg(msg p2p.Msg) error {
if msg.Size > m.maxSize {
m.maxSize = msg.Size
}
return m.rw.WriteMsg(msg)
}
// measure runs a benchmark for a single type in a single pass, with the given
// number of requests
func (pm *ProtocolManager) measure(setup *benchmarkSetup, count int) error {
clientPipe, serverPipe := p2p.MsgPipe()
clientMeteredPipe := &meteredPipe{rw: clientPipe}
serverMeteredPipe := &meteredPipe{rw: serverPipe}
var id enode.ID
rand.Read(id[:])
clientPeer := pm.newPeer(lpv2, NetworkId, p2p.NewPeer(id, "client", nil), clientMeteredPipe)
serverPeer := pm.newPeer(lpv2, NetworkId, p2p.NewPeer(id, "server", nil), serverMeteredPipe)
serverPeer.sendQueue = newExecQueue(count)
serverPeer.announceType = announceTypeNone
serverPeer.fcCosts = make(requestCostTable)
c := &requestCosts{}
for code := range requests {
serverPeer.fcCosts[code] = c
}
serverPeer.fcParams = flowcontrol.ServerParams{BufLimit: 1, MinRecharge: 1}
serverPeer.fcClient = flowcontrol.NewClientNode(pm.server.fcManager, serverPeer.fcParams)
defer serverPeer.fcClient.Disconnect()
if err := setup.req.init(pm, count); err != nil {
return err
}
errCh := make(chan error, 10)
start := mclock.Now()
go func() {
for i := 0; i < count; i++ {
if err := setup.req.request(clientPeer, i); err != nil {
errCh <- err
return
}
}
}()
go func() {
for i := 0; i < count; i++ {
if err := pm.handleMsg(serverPeer); err != nil {
errCh <- err
return
}
}
}()
go func() {
for i := 0; i < count; i++ {
msg, err := clientPipe.ReadMsg()
if err != nil {
errCh <- err
return
}
var i interface{}
msg.Decode(&i)
}
// at this point we can be sure that the other two
// goroutines finished successfully too
close(errCh)
}()
select {
case err := <-errCh:
if err != nil {
return err
}
case <-pm.quitSync:
clientPipe.Close()
serverPipe.Close()
return fmt.Errorf("Benchmark cancelled")
}
setup.totalTime += time.Duration(mclock.Now() - start)
setup.totalCount += count
setup.maxInSize = clientMeteredPipe.maxSize
setup.maxOutSize = serverMeteredPipe.maxSize
clientPipe.Close()
serverPipe.Close()
return nil
}