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642 lines
17 KiB
642 lines
17 KiB
package v0
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import (
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"fmt"
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"runtime/debug"
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"sync"
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"time"
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"github.com/tendermint/tendermint/internal/blocksync"
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"github.com/tendermint/tendermint/internal/consensus"
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"github.com/tendermint/tendermint/internal/p2p"
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sm "github.com/tendermint/tendermint/internal/state"
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"github.com/tendermint/tendermint/internal/store"
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"github.com/tendermint/tendermint/libs/log"
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"github.com/tendermint/tendermint/libs/service"
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tmsync "github.com/tendermint/tendermint/libs/sync"
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bcproto "github.com/tendermint/tendermint/proto/tendermint/blocksync"
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"github.com/tendermint/tendermint/types"
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)
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var (
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_ service.Service = (*Reactor)(nil)
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// ChannelShims contains a map of ChannelDescriptorShim objects, where each
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// object wraps a reference to a legacy p2p ChannelDescriptor and the corresponding
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// p2p proto.Message the new p2p Channel is responsible for handling.
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//
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//
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// TODO: Remove once p2p refactor is complete.
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// ref: https://github.com/tendermint/tendermint/issues/5670
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ChannelShims = map[p2p.ChannelID]*p2p.ChannelDescriptorShim{
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BlockSyncChannel: {
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MsgType: new(bcproto.Message),
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Descriptor: &p2p.ChannelDescriptor{
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ID: byte(BlockSyncChannel),
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Priority: 5,
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SendQueueCapacity: 1000,
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RecvBufferCapacity: 1024,
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RecvMessageCapacity: blocksync.MaxMsgSize,
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MaxSendBytes: 100,
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},
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},
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}
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)
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const (
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// BlockSyncChannel is a channel for blocks and status updates
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BlockSyncChannel = p2p.ChannelID(0x40)
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trySyncIntervalMS = 10
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// ask for best height every 10s
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statusUpdateIntervalSeconds = 10
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// check if we should switch to consensus reactor
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switchToConsensusIntervalSeconds = 1
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// switch to consensus after this duration of inactivity
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syncTimeout = 60 * time.Second
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)
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type consensusReactor interface {
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// For when we switch from block sync reactor to the consensus
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// machine.
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SwitchToConsensus(state sm.State, skipWAL bool)
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}
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type peerError struct {
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err error
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peerID types.NodeID
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}
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func (e peerError) Error() string {
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return fmt.Sprintf("error with peer %v: %s", e.peerID, e.err.Error())
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}
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// Reactor handles long-term catchup syncing.
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type Reactor struct {
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service.BaseService
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// immutable
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initialState sm.State
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blockExec *sm.BlockExecutor
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store *store.BlockStore
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pool *BlockPool
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consReactor consensusReactor
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blockSync *tmsync.AtomicBool
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blockSyncCh *p2p.Channel
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// blockSyncOutBridgeCh defines a channel that acts as a bridge between sending Envelope
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// messages that the reactor will consume in processBlockSyncCh and receiving messages
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// from the peer updates channel and other goroutines. We do this instead of directly
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// sending on blockSyncCh.Out to avoid race conditions in the case where other goroutines
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// send Envelopes directly to the to blockSyncCh.Out channel, since processBlockSyncCh
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// may close the blockSyncCh.Out channel at the same time that other goroutines send to
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// blockSyncCh.Out.
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blockSyncOutBridgeCh chan p2p.Envelope
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peerUpdates *p2p.PeerUpdates
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closeCh chan struct{}
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requestsCh <-chan BlockRequest
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errorsCh <-chan peerError
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// poolWG is used to synchronize the graceful shutdown of the poolRoutine and
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// requestRoutine spawned goroutines when stopping the reactor and before
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// stopping the p2p Channel(s).
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poolWG sync.WaitGroup
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metrics *consensus.Metrics
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syncStartTime time.Time
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}
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// NewReactor returns new reactor instance.
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func NewReactor(
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logger log.Logger,
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state sm.State,
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blockExec *sm.BlockExecutor,
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store *store.BlockStore,
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consReactor consensusReactor,
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blockSyncCh *p2p.Channel,
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peerUpdates *p2p.PeerUpdates,
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blockSync bool,
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metrics *consensus.Metrics,
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) (*Reactor, error) {
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if state.LastBlockHeight != store.Height() {
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return nil, fmt.Errorf("state (%v) and store (%v) height mismatch", state.LastBlockHeight, store.Height())
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}
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startHeight := store.Height() + 1
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if startHeight == 1 {
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startHeight = state.InitialHeight
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}
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requestsCh := make(chan BlockRequest, maxTotalRequesters)
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errorsCh := make(chan peerError, maxPeerErrBuffer) // NOTE: The capacity should be larger than the peer count.
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r := &Reactor{
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initialState: state,
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blockExec: blockExec,
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store: store,
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pool: NewBlockPool(startHeight, requestsCh, errorsCh),
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consReactor: consReactor,
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blockSync: tmsync.NewBool(blockSync),
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requestsCh: requestsCh,
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errorsCh: errorsCh,
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blockSyncCh: blockSyncCh,
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blockSyncOutBridgeCh: make(chan p2p.Envelope),
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peerUpdates: peerUpdates,
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closeCh: make(chan struct{}),
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metrics: metrics,
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syncStartTime: time.Time{},
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}
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r.BaseService = *service.NewBaseService(logger, "BlockSync", r)
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return r, nil
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}
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// OnStart starts separate go routines for each p2p Channel and listens for
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// envelopes on each. In addition, it also listens for peer updates and handles
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// messages on that p2p channel accordingly. The caller must be sure to execute
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// OnStop to ensure the outbound p2p Channels are closed.
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//
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// If blockSync is enabled, we also start the pool and the pool processing
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// goroutine. If the pool fails to start, an error is returned.
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func (r *Reactor) OnStart() error {
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if r.blockSync.IsSet() {
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if err := r.pool.Start(); err != nil {
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return err
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}
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r.poolWG.Add(1)
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go r.requestRoutine()
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r.poolWG.Add(1)
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go r.poolRoutine(false)
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}
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go r.processBlockSyncCh()
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go r.processPeerUpdates()
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return nil
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}
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// OnStop stops the reactor by signaling to all spawned goroutines to exit and
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// blocking until they all exit.
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func (r *Reactor) OnStop() {
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if r.blockSync.IsSet() {
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if err := r.pool.Stop(); err != nil {
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r.Logger.Error("failed to stop pool", "err", err)
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}
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}
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// wait for the poolRoutine and requestRoutine goroutines to gracefully exit
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r.poolWG.Wait()
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// Close closeCh to signal to all spawned goroutines to gracefully exit. All
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// p2p Channels should execute Close().
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close(r.closeCh)
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// Wait for all p2p Channels to be closed before returning. This ensures we
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// can easily reason about synchronization of all p2p Channels and ensure no
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// panics will occur.
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<-r.blockSyncCh.Done()
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<-r.peerUpdates.Done()
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}
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// respondToPeer loads a block and sends it to the requesting peer, if we have it.
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// Otherwise, we'll respond saying we do not have it.
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func (r *Reactor) respondToPeer(msg *bcproto.BlockRequest, peerID types.NodeID) {
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block := r.store.LoadBlock(msg.Height)
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if block != nil {
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blockProto, err := block.ToProto()
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if err != nil {
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r.Logger.Error("failed to convert msg to protobuf", "err", err)
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return
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}
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r.blockSyncCh.Out <- p2p.Envelope{
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To: peerID,
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Message: &bcproto.BlockResponse{Block: blockProto},
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}
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return
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}
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r.Logger.Info("peer requesting a block we do not have", "peer", peerID, "height", msg.Height)
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r.blockSyncCh.Out <- p2p.Envelope{
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To: peerID,
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Message: &bcproto.NoBlockResponse{Height: msg.Height},
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}
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}
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// handleBlockSyncMessage handles envelopes sent from peers on the
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// BlockSyncChannel. It returns an error only if the Envelope.Message is unknown
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// for this channel. This should never be called outside of handleMessage.
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func (r *Reactor) handleBlockSyncMessage(envelope p2p.Envelope) error {
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logger := r.Logger.With("peer", envelope.From)
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switch msg := envelope.Message.(type) {
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case *bcproto.BlockRequest:
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r.respondToPeer(msg, envelope.From)
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case *bcproto.BlockResponse:
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block, err := types.BlockFromProto(msg.Block)
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if err != nil {
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logger.Error("failed to convert block from proto", "err", err)
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return err
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}
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r.pool.AddBlock(envelope.From, block, block.Size())
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case *bcproto.StatusRequest:
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r.blockSyncCh.Out <- p2p.Envelope{
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To: envelope.From,
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Message: &bcproto.StatusResponse{
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Height: r.store.Height(),
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Base: r.store.Base(),
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},
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}
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case *bcproto.StatusResponse:
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r.pool.SetPeerRange(envelope.From, msg.Base, msg.Height)
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case *bcproto.NoBlockResponse:
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logger.Debug("peer does not have the requested block", "height", msg.Height)
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default:
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return fmt.Errorf("received unknown message: %T", msg)
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}
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return nil
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}
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// handleMessage handles an Envelope sent from a peer on a specific p2p Channel.
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// It will handle errors and any possible panics gracefully. A caller can handle
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// any error returned by sending a PeerError on the respective channel.
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func (r *Reactor) handleMessage(chID p2p.ChannelID, envelope p2p.Envelope) (err error) {
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defer func() {
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if e := recover(); e != nil {
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err = fmt.Errorf("panic in processing message: %v", e)
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r.Logger.Error(
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"recovering from processing message panic",
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"err", err,
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"stack", string(debug.Stack()),
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)
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}
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}()
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r.Logger.Debug("received message", "message", envelope.Message, "peer", envelope.From)
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switch chID {
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case BlockSyncChannel:
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err = r.handleBlockSyncMessage(envelope)
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default:
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err = fmt.Errorf("unknown channel ID (%d) for envelope (%v)", chID, envelope)
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}
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return err
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}
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// processBlockSyncCh initiates a blocking process where we listen for and handle
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// envelopes on the BlockSyncChannel and blockSyncOutBridgeCh. Any error encountered during
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// message execution will result in a PeerError being sent on the BlockSyncChannel.
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// When the reactor is stopped, we will catch the signal and close the p2p Channel
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// gracefully.
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func (r *Reactor) processBlockSyncCh() {
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defer r.blockSyncCh.Close()
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for {
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select {
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case envelope := <-r.blockSyncCh.In:
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if err := r.handleMessage(r.blockSyncCh.ID, envelope); err != nil {
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r.Logger.Error("failed to process message", "ch_id", r.blockSyncCh.ID, "envelope", envelope, "err", err)
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r.blockSyncCh.Error <- p2p.PeerError{
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NodeID: envelope.From,
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Err: err,
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}
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}
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case envelope := <-r.blockSyncOutBridgeCh:
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r.blockSyncCh.Out <- envelope
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case <-r.closeCh:
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r.Logger.Debug("stopped listening on block sync channel; closing...")
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return
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}
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}
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}
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// processPeerUpdate processes a PeerUpdate.
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func (r *Reactor) processPeerUpdate(peerUpdate p2p.PeerUpdate) {
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r.Logger.Debug("received peer update", "peer", peerUpdate.NodeID, "status", peerUpdate.Status)
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// XXX: Pool#RedoRequest can sometimes give us an empty peer.
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if len(peerUpdate.NodeID) == 0 {
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return
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}
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switch peerUpdate.Status {
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case p2p.PeerStatusUp:
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// send a status update the newly added peer
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r.blockSyncOutBridgeCh <- p2p.Envelope{
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To: peerUpdate.NodeID,
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Message: &bcproto.StatusResponse{
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Base: r.store.Base(),
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Height: r.store.Height(),
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},
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}
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case p2p.PeerStatusDown:
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r.pool.RemovePeer(peerUpdate.NodeID)
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}
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}
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// processPeerUpdates initiates a blocking process where we listen for and handle
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// PeerUpdate messages. When the reactor is stopped, we will catch the signal and
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// close the p2p PeerUpdatesCh gracefully.
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func (r *Reactor) processPeerUpdates() {
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defer r.peerUpdates.Close()
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for {
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select {
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case peerUpdate := <-r.peerUpdates.Updates():
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r.processPeerUpdate(peerUpdate)
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case <-r.closeCh:
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r.Logger.Debug("stopped listening on peer updates channel; closing...")
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return
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}
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}
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}
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// SwitchToBlockSync is called by the state sync reactor when switching to fast
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// sync.
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func (r *Reactor) SwitchToBlockSync(state sm.State) error {
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r.blockSync.Set()
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r.initialState = state
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r.pool.height = state.LastBlockHeight + 1
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if err := r.pool.Start(); err != nil {
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return err
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}
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r.syncStartTime = time.Now()
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r.poolWG.Add(1)
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go r.requestRoutine()
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r.poolWG.Add(1)
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go r.poolRoutine(true)
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return nil
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}
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func (r *Reactor) requestRoutine() {
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statusUpdateTicker := time.NewTicker(statusUpdateIntervalSeconds * time.Second)
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defer statusUpdateTicker.Stop()
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defer r.poolWG.Done()
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for {
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select {
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case <-r.closeCh:
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return
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case <-r.pool.Quit():
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return
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case request := <-r.requestsCh:
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r.blockSyncOutBridgeCh <- p2p.Envelope{
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To: request.PeerID,
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Message: &bcproto.BlockRequest{Height: request.Height},
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}
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case pErr := <-r.errorsCh:
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r.blockSyncCh.Error <- p2p.PeerError{
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NodeID: pErr.peerID,
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Err: pErr.err,
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}
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case <-statusUpdateTicker.C:
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r.poolWG.Add(1)
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go func() {
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defer r.poolWG.Done()
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r.blockSyncOutBridgeCh <- p2p.Envelope{
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Broadcast: true,
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Message: &bcproto.StatusRequest{},
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}
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}()
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}
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}
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}
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// poolRoutine handles messages from the poolReactor telling the reactor what to
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// do.
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//
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// NOTE: Don't sleep in the FOR_LOOP or otherwise slow it down!
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func (r *Reactor) poolRoutine(stateSynced bool) {
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var (
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trySyncTicker = time.NewTicker(trySyncIntervalMS * time.Millisecond)
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switchToConsensusTicker = time.NewTicker(switchToConsensusIntervalSeconds * time.Second)
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blocksSynced = uint64(0)
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chainID = r.initialState.ChainID
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state = r.initialState
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lastHundred = time.Now()
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lastRate = 0.0
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didProcessCh = make(chan struct{}, 1)
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)
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defer trySyncTicker.Stop()
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defer switchToConsensusTicker.Stop()
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defer r.poolWG.Done()
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FOR_LOOP:
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for {
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select {
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case <-switchToConsensusTicker.C:
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var (
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height, numPending, lenRequesters = r.pool.GetStatus()
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lastAdvance = r.pool.LastAdvance()
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)
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r.Logger.Debug(
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"consensus ticker",
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"num_pending", numPending,
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"total", lenRequesters,
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"height", height,
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)
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switch {
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case r.pool.IsCaughtUp():
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r.Logger.Info("switching to consensus reactor", "height", height)
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case time.Since(lastAdvance) > syncTimeout:
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r.Logger.Error("no progress since last advance", "last_advance", lastAdvance)
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default:
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r.Logger.Info(
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"not caught up yet",
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"height", height,
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"max_peer_height", r.pool.MaxPeerHeight(),
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"timeout_in", syncTimeout-time.Since(lastAdvance),
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)
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continue
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}
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if err := r.pool.Stop(); err != nil {
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r.Logger.Error("failed to stop pool", "err", err)
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}
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r.blockSync.UnSet()
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if r.consReactor != nil {
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r.consReactor.SwitchToConsensus(state, blocksSynced > 0 || stateSynced)
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}
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break FOR_LOOP
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case <-trySyncTicker.C:
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select {
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case didProcessCh <- struct{}{}:
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default:
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}
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case <-didProcessCh:
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// NOTE: It is a subtle mistake to process more than a single block at a
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// time (e.g. 10) here, because we only send one BlockRequest per loop
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// iteration. The ratio mismatch can result in starving of blocks, i.e. a
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// sudden burst of requests and responses, and repeat. Consequently, it is
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// better to split these routines rather than coupling them as it is
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// written here.
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//
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// TODO: Uncouple from request routine.
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// see if there are any blocks to sync
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first, second := r.pool.PeekTwoBlocks()
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if first == nil || second == nil {
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// we need both to sync the first block
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continue FOR_LOOP
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} else {
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// try again quickly next loop
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didProcessCh <- struct{}{}
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}
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|
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var (
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firstParts = first.MakePartSet(types.BlockPartSizeBytes)
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firstPartSetHeader = firstParts.Header()
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firstID = types.BlockID{Hash: first.Hash(), PartSetHeader: firstPartSetHeader}
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)
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// Finally, verify the first block using the second's commit.
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//
|
|
// 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.VerifyCommitLight(chainID, firstID, first.Height, second.LastCommit)
|
|
if err != nil {
|
|
err = fmt.Errorf("invalid last commit: %w", err)
|
|
r.Logger.Error(
|
|
err.Error(),
|
|
"last_commit", second.LastCommit,
|
|
"block_id", firstID,
|
|
"height", first.Height,
|
|
)
|
|
|
|
// NOTE: We've already removed the peer's request, but we still need
|
|
// to clean up the rest.
|
|
peerID := r.pool.RedoRequest(first.Height)
|
|
r.blockSyncCh.Error <- p2p.PeerError{
|
|
NodeID: peerID,
|
|
Err: err,
|
|
}
|
|
|
|
peerID2 := r.pool.RedoRequest(second.Height)
|
|
if peerID2 != peerID {
|
|
r.blockSyncCh.Error <- p2p.PeerError{
|
|
NodeID: peerID2,
|
|
Err: err,
|
|
}
|
|
}
|
|
|
|
continue FOR_LOOP
|
|
} else {
|
|
r.pool.PopRequest()
|
|
|
|
// TODO: batch saves so we do not persist to disk every block
|
|
r.store.SaveBlock(first, firstParts, second.LastCommit)
|
|
|
|
var err error
|
|
|
|
// TODO: Same thing for app - but we would need a way to get the hash
|
|
// without persisting the state.
|
|
state, err = r.blockExec.ApplyBlock(state, firstID, first)
|
|
if err != nil {
|
|
// TODO: This is bad, are we zombie?
|
|
panic(fmt.Sprintf("failed to process committed block (%d:%X): %v", first.Height, first.Hash(), err))
|
|
}
|
|
|
|
r.metrics.RecordConsMetrics(first)
|
|
|
|
blocksSynced++
|
|
|
|
if blocksSynced%100 == 0 {
|
|
lastRate = 0.9*lastRate + 0.1*(100/time.Since(lastHundred).Seconds())
|
|
r.Logger.Info(
|
|
"block sync rate",
|
|
"height", r.pool.height,
|
|
"max_peer_height", r.pool.MaxPeerHeight(),
|
|
"blocks/s", lastRate,
|
|
)
|
|
|
|
lastHundred = time.Now()
|
|
}
|
|
}
|
|
|
|
continue FOR_LOOP
|
|
|
|
case <-r.closeCh:
|
|
break FOR_LOOP
|
|
case <-r.pool.Quit():
|
|
break FOR_LOOP
|
|
}
|
|
}
|
|
}
|
|
|
|
func (r *Reactor) GetMaxPeerBlockHeight() int64 {
|
|
return r.pool.MaxPeerHeight()
|
|
}
|
|
|
|
func (r *Reactor) GetTotalSyncedTime() time.Duration {
|
|
if !r.blockSync.IsSet() || r.syncStartTime.IsZero() {
|
|
return time.Duration(0)
|
|
}
|
|
return time.Since(r.syncStartTime)
|
|
}
|
|
|
|
func (r *Reactor) GetRemainingSyncTime() time.Duration {
|
|
if !r.blockSync.IsSet() {
|
|
return time.Duration(0)
|
|
}
|
|
|
|
targetSyncs := r.pool.targetSyncBlocks()
|
|
currentSyncs := r.store.Height() - r.pool.startHeight + 1
|
|
lastSyncRate := r.pool.getLastSyncRate()
|
|
if currentSyncs < 0 || lastSyncRate < 0.001 {
|
|
return time.Duration(0)
|
|
}
|
|
|
|
remain := float64(targetSyncs-currentSyncs) / lastSyncRate
|
|
|
|
return time.Duration(int64(remain * float64(time.Second)))
|
|
}
|