Revision 1f098187707c685ad17334c43c6fdaeaf5c466b2 authored by Ethan Buchman on 16 December 2018, 17:24:54 UTC, committed by GitHub on 16 December 2018, 17:24:54 UTC
Release/v0.27.1
reactor.go
package blockchain
import (
"errors"
"fmt"
"reflect"
"time"
amino "github.com/tendermint/go-amino"
cmn "github.com/tendermint/tendermint/libs/common"
"github.com/tendermint/tendermint/libs/log"
"github.com/tendermint/tendermint/p2p"
sm "github.com/tendermint/tendermint/state"
"github.com/tendermint/tendermint/types"
)
const (
// BlockchainChannel is a channel for blocks and status updates (`BlockStore` height)
BlockchainChannel = byte(0x40)
trySyncIntervalMS = 10
// stop syncing when last block's time is
// within this much of the system time.
// stopSyncingDurationMinutes = 10
// ask for best height every 10s
statusUpdateIntervalSeconds = 10
// check if we should switch to consensus reactor
switchToConsensusIntervalSeconds = 1
// NOTE: keep up to date with bcBlockResponseMessage
bcBlockResponseMessagePrefixSize = 4
bcBlockResponseMessageFieldKeySize = 1
maxMsgSize = types.MaxBlockSizeBytes +
bcBlockResponseMessagePrefixSize +
bcBlockResponseMessageFieldKeySize
)
type consensusReactor interface {
// for when we switch from blockchain reactor and fast sync to
// the consensus machine
SwitchToConsensus(sm.State, int)
}
type peerError struct {
err error
peerID p2p.ID
}
func (e peerError) Error() string {
return fmt.Sprintf("error with peer %v: %s", e.peerID, e.err.Error())
}
// BlockchainReactor handles long-term catchup syncing.
type BlockchainReactor struct {
p2p.BaseReactor
// immutable
initialState sm.State
blockExec *sm.BlockExecutor
store *BlockStore
pool *BlockPool
fastSync bool
requestsCh <-chan BlockRequest
errorsCh <-chan peerError
}
// NewBlockchainReactor returns new reactor instance.
func NewBlockchainReactor(state sm.State, blockExec *sm.BlockExecutor, store *BlockStore,
fastSync bool) *BlockchainReactor {
if state.LastBlockHeight != store.Height() {
panic(fmt.Sprintf("state (%v) and store (%v) height mismatch", state.LastBlockHeight,
store.Height()))
}
requestsCh := make(chan BlockRequest, maxTotalRequesters)
const capacity = 1000 // must be bigger than peers count
errorsCh := make(chan peerError, capacity) // so we don't block in #Receive#pool.AddBlock
pool := NewBlockPool(
store.Height()+1,
requestsCh,
errorsCh,
)
bcR := &BlockchainReactor{
initialState: state,
blockExec: blockExec,
store: store,
pool: pool,
fastSync: fastSync,
requestsCh: requestsCh,
errorsCh: errorsCh,
}
bcR.BaseReactor = *p2p.NewBaseReactor("BlockchainReactor", bcR)
return bcR
}
// SetLogger implements cmn.Service by setting the logger on reactor and pool.
func (bcR *BlockchainReactor) SetLogger(l log.Logger) {
bcR.BaseService.Logger = l
bcR.pool.Logger = l
}
// OnStart implements cmn.Service.
func (bcR *BlockchainReactor) OnStart() error {
if bcR.fastSync {
err := bcR.pool.Start()
if err != nil {
return err
}
go bcR.poolRoutine()
}
return nil
}
// OnStop implements cmn.Service.
func (bcR *BlockchainReactor) OnStop() {
bcR.pool.Stop()
}
// GetChannels implements Reactor
func (bcR *BlockchainReactor) GetChannels() []*p2p.ChannelDescriptor {
return []*p2p.ChannelDescriptor{
{
ID: BlockchainChannel,
Priority: 10,
SendQueueCapacity: 1000,
RecvBufferCapacity: 50 * 4096,
RecvMessageCapacity: maxMsgSize,
},
}
}
// AddPeer implements Reactor by sending our state to peer.
func (bcR *BlockchainReactor) AddPeer(peer p2p.Peer) {
msgBytes := cdc.MustMarshalBinaryBare(&bcStatusResponseMessage{bcR.store.Height()})
if !peer.Send(BlockchainChannel, msgBytes) {
// doing nothing, will try later in `poolRoutine`
}
// peer is added to the pool once we receive the first
// bcStatusResponseMessage from the peer and call pool.SetPeerHeight
}
// RemovePeer implements Reactor by removing peer from the pool.
func (bcR *BlockchainReactor) RemovePeer(peer p2p.Peer, reason interface{}) {
bcR.pool.RemovePeer(peer.ID())
}
// respondToPeer loads a block and sends it to the requesting peer,
// if we have it. Otherwise, we'll respond saying we don't have it.
// According to the Tendermint spec, if all nodes are honest,
// no node should be requesting for a block that's non-existent.
func (bcR *BlockchainReactor) respondToPeer(msg *bcBlockRequestMessage,
src p2p.Peer) (queued bool) {
block := bcR.store.LoadBlock(msg.Height)
if block != nil {
msgBytes := cdc.MustMarshalBinaryBare(&bcBlockResponseMessage{Block: block})
return src.TrySend(BlockchainChannel, msgBytes)
}
bcR.Logger.Info("Peer asking for a block we don't have", "src", src, "height", msg.Height)
msgBytes := cdc.MustMarshalBinaryBare(&bcNoBlockResponseMessage{Height: msg.Height})
return src.TrySend(BlockchainChannel, msgBytes)
}
// Receive implements Reactor by handling 4 types of messages (look below).
func (bcR *BlockchainReactor) Receive(chID byte, src p2p.Peer, msgBytes []byte) {
msg, err := decodeMsg(msgBytes)
if err != nil {
bcR.Logger.Error("Error decoding message", "src", src, "chId", chID, "msg", msg, "err", err, "bytes", msgBytes)
bcR.Switch.StopPeerForError(src, err)
return
}
if err = msg.ValidateBasic(); err != nil {
bcR.Logger.Error("Peer sent us invalid msg", "peer", src, "msg", msg, "err", err)
bcR.Switch.StopPeerForError(src, err)
return
}
bcR.Logger.Debug("Receive", "src", src, "chID", chID, "msg", msg)
switch msg := msg.(type) {
case *bcBlockRequestMessage:
if queued := bcR.respondToPeer(msg, src); !queued {
// Unfortunately not queued since the queue is full.
}
case *bcBlockResponseMessage:
bcR.pool.AddBlock(src.ID(), msg.Block, len(msgBytes))
case *bcStatusRequestMessage:
// Send peer our state.
msgBytes := cdc.MustMarshalBinaryBare(&bcStatusResponseMessage{bcR.store.Height()})
queued := src.TrySend(BlockchainChannel, msgBytes)
if !queued {
// sorry
}
case *bcStatusResponseMessage:
// Got a peer status. Unverified.
bcR.pool.SetPeerHeight(src.ID(), msg.Height)
default:
bcR.Logger.Error(fmt.Sprintf("Unknown message type %v", reflect.TypeOf(msg)))
}
}
// Handle messages from the poolReactor telling the reactor what to do.
// NOTE: Don't sleep in the FOR_LOOP or otherwise slow it down!
func (bcR *BlockchainReactor) poolRoutine() {
trySyncTicker := time.NewTicker(trySyncIntervalMS * time.Millisecond)
statusUpdateTicker := time.NewTicker(statusUpdateIntervalSeconds * time.Second)
switchToConsensusTicker := time.NewTicker(switchToConsensusIntervalSeconds * time.Second)
blocksSynced := 0
chainID := bcR.initialState.ChainID
state := bcR.initialState
lastHundred := time.Now()
lastRate := 0.0
didProcessCh := make(chan struct{}, 1)
FOR_LOOP:
for {
select {
case request := <-bcR.requestsCh:
peer := bcR.Switch.Peers().Get(request.PeerID)
if peer == nil {
continue FOR_LOOP // Peer has since been disconnected.
}
msgBytes := cdc.MustMarshalBinaryBare(&bcBlockRequestMessage{request.Height})
queued := peer.TrySend(BlockchainChannel, msgBytes)
if !queued {
// We couldn't make the request, send-queue full.
// The pool handles timeouts, just let it go.
continue FOR_LOOP
}
case err := <-bcR.errorsCh:
peer := bcR.Switch.Peers().Get(err.peerID)
if peer != nil {
bcR.Switch.StopPeerForError(peer, err)
}
case <-statusUpdateTicker.C:
// ask for status updates
go bcR.BroadcastStatusRequest() // nolint: errcheck
case <-switchToConsensusTicker.C:
height, numPending, lenRequesters := bcR.pool.GetStatus()
outbound, inbound, _ := bcR.Switch.NumPeers()
bcR.Logger.Debug("Consensus ticker", "numPending", numPending, "total", lenRequesters,
"outbound", outbound, "inbound", inbound)
if bcR.pool.IsCaughtUp() {
bcR.Logger.Info("Time to switch to consensus reactor!", "height", height)
bcR.pool.Stop()
conR, ok := bcR.Switch.Reactor("CONSENSUS").(consensusReactor)
if ok {
conR.SwitchToConsensus(state, blocksSynced)
} else {
// should only happen during testing
}
break FOR_LOOP
}
case <-trySyncTicker.C: // chan time
select {
case didProcessCh <- struct{}{}:
default:
}
case <-didProcessCh:
// NOTE: It is a subtle mistake to process more than a single block
// at a time (e.g. 10) here, because we only TrySend 1 request per
// loop. The ratio mismatch can result in starving of blocks, a
// sudden burst of requests and responses, and repeat.
// Consequently, it is better to split these routines rather than
// coupling them as it's written here. TODO uncouple from request
// routine.
// See if there are any blocks to sync.
first, second := bcR.pool.PeekTwoBlocks()
//bcR.Logger.Info("TrySync peeked", "first", first, "second", second)
if first == nil || second == nil {
// We need both to sync the first block.
continue FOR_LOOP
} else {
// Try again quickly next loop.
didProcessCh <- struct{}{}
}
firstParts := first.MakePartSet(types.BlockPartSizeBytes)
firstPartsHeader := firstParts.Header()
firstID := types.BlockID{first.Hash(), firstPartsHeader}
// Finally, verify the first block using the second's commit
// NOTE: we can probably make this more efficient, but note that calling
// first.Hash() doesn't verify the tx contents, so MakePartSet() is
// currently necessary.
err := state.Validators.VerifyCommit(
chainID, firstID, first.Height, second.LastCommit)
if err != nil {
bcR.Logger.Error("Error in validation", "err", err)
peerID := bcR.pool.RedoRequest(first.Height)
peer := bcR.Switch.Peers().Get(peerID)
if peer != nil {
// NOTE: we've already removed the peer's request, but we
// still need to clean up the rest.
bcR.Switch.StopPeerForError(peer, fmt.Errorf("BlockchainReactor validation error: %v", err))
}
peerID2 := bcR.pool.RedoRequest(second.Height)
peer2 := bcR.Switch.Peers().Get(peerID2)
if peer2 != nil && peer2 != peer {
// NOTE: we've already removed the peer's request, but we
// still need to clean up the rest.
bcR.Switch.StopPeerForError(peer2, fmt.Errorf("BlockchainReactor validation error: %v", err))
}
continue FOR_LOOP
} else {
bcR.pool.PopRequest()
// TODO: batch saves so we dont persist to disk every block
bcR.store.SaveBlock(first, firstParts, second.LastCommit)
// TODO: same thing for app - but we would need a way to
// get the hash without persisting the state
var err error
state, err = bcR.blockExec.ApplyBlock(state, firstID, first)
if err != nil {
// TODO This is bad, are we zombie?
cmn.PanicQ(fmt.Sprintf("Failed to process committed block (%d:%X): %v",
first.Height, first.Hash(), err))
}
blocksSynced++
if blocksSynced%100 == 0 {
lastRate = 0.9*lastRate + 0.1*(100/time.Since(lastHundred).Seconds())
bcR.Logger.Info("Fast Sync Rate", "height", bcR.pool.height,
"max_peer_height", bcR.pool.MaxPeerHeight(), "blocks/s", lastRate)
lastHundred = time.Now()
}
}
continue FOR_LOOP
case <-bcR.Quit():
break FOR_LOOP
}
}
}
// BroadcastStatusRequest broadcasts `BlockStore` height.
func (bcR *BlockchainReactor) BroadcastStatusRequest() error {
msgBytes := cdc.MustMarshalBinaryBare(&bcStatusRequestMessage{bcR.store.Height()})
bcR.Switch.Broadcast(BlockchainChannel, msgBytes)
return nil
}
//-----------------------------------------------------------------------------
// Messages
// BlockchainMessage is a generic message for this reactor.
type BlockchainMessage interface {
ValidateBasic() error
}
func RegisterBlockchainMessages(cdc *amino.Codec) {
cdc.RegisterInterface((*BlockchainMessage)(nil), nil)
cdc.RegisterConcrete(&bcBlockRequestMessage{}, "tendermint/blockchain/BlockRequest", nil)
cdc.RegisterConcrete(&bcBlockResponseMessage{}, "tendermint/blockchain/BlockResponse", nil)
cdc.RegisterConcrete(&bcNoBlockResponseMessage{}, "tendermint/blockchain/NoBlockResponse", nil)
cdc.RegisterConcrete(&bcStatusResponseMessage{}, "tendermint/blockchain/StatusResponse", nil)
cdc.RegisterConcrete(&bcStatusRequestMessage{}, "tendermint/blockchain/StatusRequest", nil)
}
func decodeMsg(bz []byte) (msg BlockchainMessage, err error) {
if len(bz) > maxMsgSize {
return msg, fmt.Errorf("Msg exceeds max size (%d > %d)", len(bz), maxMsgSize)
}
err = cdc.UnmarshalBinaryBare(bz, &msg)
return
}
//-------------------------------------
type bcBlockRequestMessage struct {
Height int64
}
// ValidateBasic performs basic validation.
func (m *bcBlockRequestMessage) ValidateBasic() error {
if m.Height < 0 {
return errors.New("Negative Height")
}
return nil
}
func (m *bcBlockRequestMessage) String() string {
return fmt.Sprintf("[bcBlockRequestMessage %v]", m.Height)
}
type bcNoBlockResponseMessage struct {
Height int64
}
// ValidateBasic performs basic validation.
func (m *bcNoBlockResponseMessage) ValidateBasic() error {
if m.Height < 0 {
return errors.New("Negative Height")
}
return nil
}
func (brm *bcNoBlockResponseMessage) String() string {
return fmt.Sprintf("[bcNoBlockResponseMessage %d]", brm.Height)
}
//-------------------------------------
type bcBlockResponseMessage struct {
Block *types.Block
}
// ValidateBasic performs basic validation.
func (m *bcBlockResponseMessage) ValidateBasic() error {
if err := m.Block.ValidateBasic(); err != nil {
return err
}
return nil
}
func (m *bcBlockResponseMessage) String() string {
return fmt.Sprintf("[bcBlockResponseMessage %v]", m.Block.Height)
}
//-------------------------------------
type bcStatusRequestMessage struct {
Height int64
}
// ValidateBasic performs basic validation.
func (m *bcStatusRequestMessage) ValidateBasic() error {
if m.Height < 0 {
return errors.New("Negative Height")
}
return nil
}
func (m *bcStatusRequestMessage) String() string {
return fmt.Sprintf("[bcStatusRequestMessage %v]", m.Height)
}
//-------------------------------------
type bcStatusResponseMessage struct {
Height int64
}
// ValidateBasic performs basic validation.
func (m *bcStatusResponseMessage) ValidateBasic() error {
if m.Height < 0 {
return errors.New("Negative Height")
}
return nil
}
func (m *bcStatusResponseMessage) String() string {
return fmt.Sprintf("[bcStatusResponseMessage %v]", m.Height)
}
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