feat: reduce allocations

After profiling allocations on a bootstrap node, I've noticed that
peerInfoToPBPeer is a very heavy source of allocations. This change should
improve the situation significantly.

Author: Stebalien

go.mod

@@ -28,7 +28,6 @@ require (
 	github.com/libp2p/go-netroute v0.1.2
 	github.com/multiformats/go-base32 v0.0.3
 	github.com/multiformats/go-multiaddr v0.2.1
-	github.com/multiformats/go-multiaddr-dns v0.2.0
 	github.com/multiformats/go-multiaddr-net v0.1.4
 	github.com/multiformats/go-multihash v0.0.13
 	github.com/multiformats/go-multistream v0.1.1

pb/bytestring.go

@@ -0,0 +1,42 @@
+package dht_pb
+
+import (
+	"encoding/json"
+)
+
+type byteString string
+
+func (b byteString) Marshal() ([]byte, error) {
+	return []byte(b), nil
+}
+
+func (b *byteString) MarshalTo(data []byte) (int, error) {
+	return copy(data, *b), nil
+}
+
+func (b *byteString) Unmarshal(data []byte) error {
+	*b = byteString(data)
+	return nil
+}
+
+func (b *byteString) Size() int {
+	return len(*b)
+}
+
+func (b byteString) MarshalJSON() ([]byte, error) {
+	return json.Marshal([]byte(b))
+}
+
+func (b *byteString) UnmarshalJSON(data []byte) error {
+	var buf []byte
+	err := json.Unmarshal(data, &buf)
+	if err != nil {
+		return err
+	}
+	*b = byteString(buf)
+	return nil
+}
+
+func (b byteString) Equal(other byteString) bool {
+	return b == other
+}

pb/dht.pb.go

@@ -9,6 +9,7 @@ syntax = "proto3";
 package dht.pb;
 
 import "github.com/libp2p/go-libp2p-record/pb/record.proto";
+import "github.com/gogo/protobuf/gogoproto/gogo.proto";
 
 message Message {
 	enum MessageType {
@@ -37,7 +38,7 @@ message Message {
 
 	message Peer {
 		// ID of a given peer.
-		bytes id = 1;
+		bytes id = 1 [(gogoproto.customtype) = "byteString", (gogoproto.nullable) = false];
 
 		// multiaddrs for a given peer
 		repeated bytes addrs = 2;
@@ -63,9 +64,9 @@ message Message {
 
 	// Used to return peers closer to a key in a query
 	// GET_VALUE, GET_PROVIDERS, FIND_NODE
-	repeated Peer closerPeers = 8;
+	repeated Peer closerPeers = 8 [(gogoproto.nullable) = false];
 
 	// Used to return Providers
 	// GET_VALUE, ADD_PROVIDER, GET_PROVIDERS
-	repeated Peer providerPeers = 9;
+	repeated Peer providerPeers = 9 [(gogoproto.nullable) = false];
 }

pb/dht.proto

@@ -25,43 +25,41 @@ func NewMessage(typ Message_MessageType, key []byte, level int) *Message {
 	return m
 }
 
-func peerRoutingInfoToPBPeer(p PeerRoutingInfo) *Message_Peer {
-	pbp := new(Message_Peer)
+func peerRoutingInfoToPBPeer(p PeerRoutingInfo) Message_Peer {
+	var pbp Message_Peer
 
 	pbp.Addrs = make([][]byte, len(p.Addrs))
 	for i, maddr := range p.Addrs {
 		pbp.Addrs[i] = maddr.Bytes() // Bytes, not String. Compressed.
 	}
-	s := string(p.ID)
-	pbp.Id = []byte(s)
-	c := ConnectionType(p.Connectedness)
-	pbp.Connection = c
+	pbp.Id = byteString(p.ID)
+	pbp.Connection = ConnectionType(p.Connectedness)
 	return pbp
 }
 
-func peerInfoToPBPeer(p peer.AddrInfo) *Message_Peer {
-	pbp := new(Message_Peer)
+func peerInfoToPBPeer(p peer.AddrInfo) Message_Peer {
+	var pbp Message_Peer
 
 	pbp.Addrs = make([][]byte, len(p.Addrs))
 	for i, maddr := range p.Addrs {
 		pbp.Addrs[i] = maddr.Bytes() // Bytes, not String. Compressed.
 	}
-	pbp.Id = []byte(p.ID)
+	pbp.Id = byteString(p.ID)
 	return pbp
 }
 
 // PBPeerToPeer turns a *Message_Peer into its peer.AddrInfo counterpart
-func PBPeerToPeerInfo(pbp *Message_Peer) *peer.AddrInfo {
-	return &peer.AddrInfo{
-		ID:    peer.ID(pbp.GetId()),
+func PBPeerToPeerInfo(pbp Message_Peer) peer.AddrInfo {
+	return peer.AddrInfo{
+		ID:    peer.ID(pbp.Id),
 		Addrs: pbp.Addresses(),
 	}
 }
 
 // RawPeerInfosToPBPeers converts a slice of Peers into a slice of *Message_Peers,
 // ready to go out on the wire.
-func RawPeerInfosToPBPeers(peers []peer.AddrInfo) []*Message_Peer {
-	pbpeers := make([]*Message_Peer, len(peers))
+func RawPeerInfosToPBPeers(peers []peer.AddrInfo) []Message_Peer {
+	pbpeers := make([]Message_Peer, len(peers))
 	for i, p := range peers {
 		pbpeers[i] = peerInfoToPBPeer(p)
 	}
@@ -72,7 +70,7 @@ func RawPeerInfosToPBPeers(peers []peer.AddrInfo) []*Message_Peer {
 // which can be written to a message and sent out. the key thing this function
 // does (in addition to PeersToPBPeers) is set the ConnectionType with
 // information from the given network.Network.
-func PeerInfosToPBPeers(n network.Network, peers []peer.AddrInfo) []*Message_Peer {
+func PeerInfosToPBPeers(n network.Network, peers []peer.AddrInfo) []Message_Peer {
 	pbps := RawPeerInfosToPBPeers(peers)
 	for i, pbp := range pbps {
 		c := ConnectionType(n.Connectedness(peers[i].ID))
@@ -81,8 +79,8 @@ func PeerInfosToPBPeers(n network.Network, peers []peer.AddrInfo) []*Message_Pee
 	return pbps
 }
 
-func PeerRoutingInfosToPBPeers(peers []PeerRoutingInfo) []*Message_Peer {
-	pbpeers := make([]*Message_Peer, len(peers))
+func PeerRoutingInfosToPBPeers(peers []PeerRoutingInfo) []Message_Peer {
+	pbpeers := make([]Message_Peer, len(peers))
 	for i, p := range peers {
 		pbpeers[i] = peerRoutingInfoToPBPeer(p)
 	}
@@ -91,10 +89,11 @@ func PeerRoutingInfosToPBPeers(peers []PeerRoutingInfo) []*Message_Peer {
 
 // PBPeersToPeerInfos converts given []*Message_Peer into []peer.AddrInfo
 // Invalid addresses will be silently omitted.
-func PBPeersToPeerInfos(pbps []*Message_Peer) []*peer.AddrInfo {
+func PBPeersToPeerInfos(pbps []Message_Peer) []*peer.AddrInfo {
 	peers := make([]*peer.AddrInfo, 0, len(pbps))
 	for _, pbp := range pbps {
-		peers = append(peers, PBPeerToPeerInfo(pbp))
+		ai := PBPeerToPeerInfo(pbp)
+		peers = append(peers, &ai)
 	}
 	return peers
 }
@@ -109,7 +108,7 @@ func (m *Message_Peer) Addresses() []ma.Multiaddr {
 	for _, addr := range m.Addrs {
 		maddr, err := ma.NewMultiaddrBytes(addr)
 		if err != nil {
-			log.Debugw("error decoding multiaddr for peer", "peer", m.GetId(), "error", err)
+			log.Debugw("error decoding multiaddr for peer", "peer", peer.ID(m.Id), "error", err)
 			continue
 		}