bitswap/server: remove provide

We always had a very weird relationship between bitswap and providing.
Bitswap took care of doing the initial provide and then reprovider did it later.
The Bitswap server had a complicated providing workflow where it slurped thing into memory.

Reprovide accepts provides and is able to queue them in a database, such as on disk, this is much better.

I'll add options to hook initial provide logic from the blockservice to the reprovider queue so consumers don't have to do this themselves.

Author: Jorropo

CHANGELOG.md

@@ -22,6 +22,8 @@ The following emojis are used to highlight certain changes:
 
 ### Removed
 
+- 🛠 `bitswap` & `bitswap/server` no longer provide to content routers, instead you can use the `provider` package because it uses a datastore queue and batches calls to ProvideMany.
+
 ### Security
 
 ## [v0.16.0]

bitswap/bitswap.go

@@ -5,7 +5,6 @@ import (
 	"fmt"
 
 	"github.com/ipfs/boxo/bitswap/client"
-	"github.com/ipfs/boxo/bitswap/internal/defaults"
 	"github.com/ipfs/boxo/bitswap/message"
 	"github.com/ipfs/boxo/bitswap/network"
 	"github.com/ipfs/boxo/bitswap/server"
@@ -45,9 +44,8 @@ type bitswap interface {
 }
 
 var (
-	_                  exchange.SessionExchange = (*Bitswap)(nil)
-	_                  bitswap                  = (*Bitswap)(nil)
-	HasBlockBufferSize                          = defaults.HasBlockBufferSize
+	_ exchange.SessionExchange = (*Bitswap)(nil)
+	_ bitswap                  = (*Bitswap)(nil)
 )
 
 type Bitswap struct {
@@ -85,10 +83,6 @@ func New(ctx context.Context, net network.BitSwapNetwork, bstore blockstore.Bloc
 		serverOptions = append(serverOptions, server.WithTracer(tracer))
 	}
 
-	if HasBlockBufferSize != defaults.HasBlockBufferSize {
-		serverOptions = append(serverOptions, server.HasBlockBufferSize(HasBlockBufferSize))
-	}
-
 	ctx = metrics.CtxSubScope(ctx, "bitswap")
 
 	bs.Server = server.New(ctx, net, bstore, serverOptions...)
@@ -115,7 +109,6 @@ type Stat struct {
 	MessagesReceived uint64
 	BlocksSent       uint64
 	DataSent         uint64
-	ProvideBufLen    int
 }
 
 func (bs *Bitswap) Stat() (*Stat, error) {
@@ -138,7 +131,6 @@ func (bs *Bitswap) Stat() (*Stat, error) {
 		Peers:            ss.Peers,
 		BlocksSent:       ss.BlocksSent,
 		DataSent:         ss.DataSent,
-		ProvideBufLen:    ss.ProvideBufLen,
 	}, nil
 }
 

bitswap/bitswap_test.go

@@ -120,7 +120,7 @@ func TestGetBlockFromPeerAfterPeerAnnounces(t *testing.T) {
 func TestDoesNotProvideWhenConfiguredNotTo(t *testing.T) {
 	net := tn.VirtualNetwork(mockrouting.NewServer(), delay.Fixed(kNetworkDelay))
 	block := blocks.NewBlock([]byte("block"))
-	bsOpts := []bitswap.Option{bitswap.ProvideEnabled(false), bitswap.ProviderSearchDelay(50 * time.Millisecond)}
+	bsOpts := []bitswap.Option{bitswap.ProviderSearchDelay(50 * time.Millisecond)}
 	ig := testinstance.NewTestInstanceGenerator(net, nil, bsOpts)
 	defer ig.Close()
 

bitswap/client/bitswap_with_sessions_test.go

@@ -37,6 +37,10 @@ func addBlock(t *testing.T, ctx context.Context, inst testinstance.Instance, blk
 	if err != nil {
 		t.Fatal(err)
 	}
+	err = inst.Adapter.Provide(ctx, blk.Cid())
+	if err != nil {
+		t.Fatal(err)
+	}
 }
 
 func TestBasicSessions(t *testing.T) {

bitswap/internal/defaults/defaults.go

@@ -20,11 +20,6 @@ const (
 	BitswapMaxOutstandingBytesPerPeer = 1 << 20
 	// the number of bytes we attempt to make each outgoing bitswap message
 	BitswapEngineTargetMessageSize = 16 * 1024
-	// HasBlockBufferSize is the buffer size of the channel for new blocks
-	// that need to be provided. They should get pulled over by the
-	// provideCollector even before they are actually provided.
-	// TODO: Does this need to be this large givent that?
-	HasBlockBufferSize = 256
 
 	// Maximum size of the wantlist we are willing to keep in memory.
 	MaxQueuedWantlistEntiresPerPeer = 1024

bitswap/options.go

@@ -43,10 +43,6 @@ func TaskWorkerCount(count int) Option {
 	return Option{server.TaskWorkerCount(count)}
 }
 
-func ProvideEnabled(enabled bool) Option {
-	return Option{server.ProvideEnabled(enabled)}
-}
-
 func SetSendDontHaves(send bool) Option {
 	return Option{server.SetSendDontHaves(send)}
 }

bitswap/server/server.go

@@ -21,20 +21,15 @@ import (
 	logging "github.com/ipfs/go-log/v2"
 	"github.com/ipfs/go-metrics-interface"
 	process "github.com/jbenet/goprocess"
-	procctx "github.com/jbenet/goprocess/context"
 	"github.com/libp2p/go-libp2p/core/peer"
 	"go.uber.org/zap"
 )
 
-var provideKeysBufferSize = 2048
-
 var (
 	log   = logging.Logger("bitswap-server")
 	sflog = log.Desugar()
 )
 
-const provideWorkerMax = 6
-
 type Option func(*Server)
 
 type Server struct {
@@ -59,20 +54,8 @@ type Server struct {
 
 	process process.Process
 
-	// newBlocks is a channel for newly added blocks to be provided to the
-	// network.  blocks pushed down this channel get buffered and fed to the
-	// provideKeys channel later on to avoid too much network activity
-	newBlocks chan cid.Cid
-	// provideKeys directly feeds provide workers
-	provideKeys chan cid.Cid
-
 	// Extra options to pass to the decision manager
 	engineOptions []decision.Option
-
-	// the size of channel buffer to use
-	hasBlockBufferSize int
-	// whether or not to make provide announcements
-	provideEnabled bool
 }
 
 func New(ctx context.Context, network bsnet.BitSwapNetwork, bstore blockstore.Blockstore, options ...Option) *Server {
@@ -87,16 +70,12 @@ func New(ctx context.Context, network bsnet.BitSwapNetwork, bstore blockstore.Bl
 	}()
 
 	s := &Server{
-		sentHistogram:      bmetrics.SentHist(ctx),
-		sendTimeHistogram:  bmetrics.SendTimeHist(ctx),
-		taskWorkerCount:    defaults.BitswapTaskWorkerCount,
-		network:            network,
-		process:            px,
-		provideEnabled:     true,
-		hasBlockBufferSize: defaults.HasBlockBufferSize,
-		provideKeys:        make(chan cid.Cid, provideKeysBufferSize),
+		sentHistogram:     bmetrics.SentHist(ctx),
+		sendTimeHistogram: bmetrics.SendTimeHist(ctx),
+		taskWorkerCount:   defaults.BitswapTaskWorkerCount,
+		network:           network,
+		process:           px,
 	}
-	s.newBlocks = make(chan cid.Cid, s.hasBlockBufferSize)
 
 	for _, o := range options {
 		o(s)
@@ -131,13 +110,6 @@ func WithTracer(tap tracer.Tracer) Option {
 	}
 }
 
-// ProvideEnabled is an option for enabling/disabling provide announcements
-func ProvideEnabled(enabled bool) Option {
-	return func(bs *Server) {
-		bs.provideEnabled = enabled
-	}
-}
-
 func WithPeerBlockRequestFilter(pbrf decision.PeerBlockRequestFilter) Option {
 	o := decision.WithPeerBlockRequestFilter(pbrf)
 	return func(bs *Server) {
@@ -233,16 +205,6 @@ func MaxCidSize(n uint) Option {
 	}
 }
 
-// HasBlockBufferSize configure how big the new blocks buffer should be.
-func HasBlockBufferSize(count int) Option {
-	if count < 0 {
-		panic("cannot have negative buffer size")
-	}
-	return func(bs *Server) {
-		bs.hasBlockBufferSize = count
-	}
-}
-
 // WantlistForPeer returns the currently understood list of blocks requested by a
 // given peer.
 func (bs *Server) WantlistForPeer(p peer.ID) []cid.Cid {
@@ -263,18 +225,6 @@ func (bs *Server) startWorkers(ctx context.Context, px process.Process) {
 			bs.taskWorker(ctx, i)
 		})
 	}
-
-	if bs.provideEnabled {
-		// Start up a worker to manage sending out provides messages
-		px.Go(func(px process.Process) {
-			bs.provideCollector(ctx)
-		})
-
-		// Spawn up multiple workers to handle incoming blocks
-		// consider increasing number if providing blocks bottlenecks
-		// file transfers
-		px.Go(bs.provideWorker)
-	}
 }
 
 func (bs *Server) taskWorker(ctx context.Context, id int) {
@@ -382,18 +332,16 @@ func (bs *Server) sendBlocks(ctx context.Context, env *decision.Envelope) {
 }
 
 type Stat struct {
-	Peers         []string
-	ProvideBufLen int
-	BlocksSent    uint64
-	DataSent      uint64
+	Peers      []string
+	BlocksSent uint64
+	DataSent   uint64
 }
 
 // Stat returns aggregated statistics about bitswap operations
 func (bs *Server) Stat() (Stat, error) {
 	bs.counterLk.Lock()
 	s := bs.counters
 	bs.counterLk.Unlock()
-	s.ProvideBufLen = len(bs.newBlocks)
 
 	peers := bs.engine.Peers()
 	peersStr := make([]string, len(peers))
@@ -420,107 +368,9 @@ func (bs *Server) NotifyNewBlocks(ctx context.Context, blks ...blocks.Block) err
 	// Send wanted blocks to decision engine
 	bs.engine.NotifyNewBlocks(blks)
 
-	// If the reprovider is enabled, send block to reprovider
-	if bs.provideEnabled {
-		for _, blk := range blks {
-			select {
-			case bs.newBlocks <- blk.Cid():
-				// send block off to be reprovided
-			case <-bs.process.Closing():
-				return bs.process.Close()
-			}
-		}
-	}
-
 	return nil
 }
 
-func (bs *Server) provideCollector(ctx context.Context) {
-	defer close(bs.provideKeys)
-	var toProvide []cid.Cid
-	var nextKey cid.Cid
-	var keysOut chan cid.Cid
-
-	for {
-		select {
-		case blkey, ok := <-bs.newBlocks:
-			if !ok {
-				log.Debug("newBlocks channel closed")
-				return
-			}
-
-			if keysOut == nil {
-				nextKey = blkey
-				keysOut = bs.provideKeys
-			} else {
-				toProvide = append(toProvide, blkey)
-			}
-		case keysOut <- nextKey:
-			if len(toProvide) > 0 {
-				nextKey = toProvide[0]
-				toProvide = toProvide[1:]
-			} else {
-				keysOut = nil
-			}
-		case <-ctx.Done():
-			return
-		}
-	}
-}
-
-func (bs *Server) provideWorker(px process.Process) {
-	// FIXME: OnClosingContext returns a _custom_ context type.
-	// Unfortunately, deriving a new cancelable context from this custom
-	// type fires off a goroutine. To work around this, we create a single
-	// cancelable context up-front and derive all sub-contexts from that.
-	//
-	// See: https://github.com/ipfs/go-ipfs/issues/5810
-	ctx := procctx.OnClosingContext(px)
-	ctx, cancel := context.WithCancel(ctx)
-	defer cancel()
-
-	limit := make(chan struct{}, provideWorkerMax)
-
-	limitedGoProvide := func(k cid.Cid, wid int) {
-		defer func() {
-			// replace token when done
-			<-limit
-		}()
-
-		log.Debugw("Bitswap.ProvideWorker.Start", "ID", wid, "cid", k)
-		defer log.Debugw("Bitswap.ProvideWorker.End", "ID", wid, "cid", k)
-
-		ctx, cancel := context.WithTimeout(ctx, defaults.ProvideTimeout) // timeout ctx
-		defer cancel()
-
-		if err := bs.network.Provide(ctx, k); err != nil {
-			log.Warn(err)
-		}
-	}
-
-	// worker spawner, reads from bs.provideKeys until it closes, spawning a
-	// _ratelimited_ number of workers to handle each key.
-	for wid := 2; ; wid++ {
-		log.Debug("Bitswap.ProvideWorker.Loop")
-
-		select {
-		case <-px.Closing():
-			return
-		case k, ok := <-bs.provideKeys:
-			if !ok {
-				log.Debug("provideKeys channel closed")
-				return
-			}
-			select {
-			case <-px.Closing():
-				return
-			case limit <- struct{}{}:
-				go limitedGoProvide(k, wid)
-			}
-		}
-	}
-}
-
 func (bs *Server) ReceiveMessage(ctx context.Context, p peer.ID, incoming message.BitSwapMessage) {
 	// This call records changes to wantlists, blocks received,
 	// and number of bytes transfered.