feat: cleanup protocol resources on shutdown

Fixes #148

Author: agaffney

Makefile

@@ -1,25 +1,28 @@
-BINARY=go-ouroboros-network
-
 # Determine root directory
 ROOT_DIR=$(shell dirname $(realpath $(firstword $(MAKEFILE_LIST))))
 
 # Gather all .go files for use in dependencies below
 GO_FILES=$(shell find $(ROOT_DIR) -name '*.go')
 
-# Build our program binary
-# Depends on GO_FILES to determine when rebuild is needed
-$(BINARY): $(GO_FILES)
-	# Needed to fetch new dependencies and add them to go.mod
-	go mod tidy
-	go build -o $(BINARY) ./cmd/$(BINARY)
+# Gather list of expected binaries
+BINARIES=$(shell cd $(ROOT_DIR)/cmd && ls -1)
 
-.PHONY: build clean test
+.PHONY: build mod-tidy clean test
 
 # Alias for building program binary
-build: $(BINARY)
+build: $(BINARIES)
+
+mod-tidy:
+	# Needed to fetch new dependencies and add them to go.mod
+	go mod tidy
 
 clean:
-	rm -f $(BINARY)
+	rm -f $(BINARIES)
 
 test:
 	go test -v ./...
+
+# Build our program binaries
+# Depends on GO_FILES to determine when rebuild is needed
+$(BINARIES): mod-tidy $(GO_FILES)
+	go build -o $(@) ./cmd/$(@)

cmd/go-ouroboros-network/main.go

@@ -78,6 +78,8 @@ func main() {
 			testServer(f)
 		case "query":
 			testQuery(f)
+		case "mem-usage":
+			testMemUsage(f)
 		default:
 			fmt.Printf("Unknown subcommand: %s\n", f.flagset.Arg(0))
 			os.Exit(1)

cmd/go-ouroboros-network/mem_usage.go

@@ -0,0 +1,110 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"log"
+	"net/http"
+	_ "net/http/pprof"
+	"os"
+	"runtime"
+	"runtime/pprof"
+	"time"
+
+	ouroboros "github.com/cloudstruct/go-ouroboros-network"
+)
+
+type memUsageFlags struct {
+	flagset   *flag.FlagSet
+	startEra  string
+	tip       bool
+	debugPort int
+}
+
+func newMemUsageFlags() *memUsageFlags {
+	f := &memUsageFlags{
+		flagset: flag.NewFlagSet("mem-usage", flag.ExitOnError),
+	}
+	f.flagset.StringVar(&f.startEra, "start-era", "genesis", "era which to start chain-sync at")
+	f.flagset.BoolVar(&f.tip, "tip", false, "start chain-sync at current chain tip")
+	f.flagset.IntVar(&f.debugPort, "debug-port", 8080, "pprof port")
+	return f
+}
+
+func testMemUsage(f *globalFlags) {
+	memUsageFlags := newMemUsageFlags()
+	err := memUsageFlags.flagset.Parse(f.flagset.Args()[1:])
+	if err != nil {
+		fmt.Printf("failed to parse subcommand args: %s\n", err)
+		os.Exit(1)
+	}
+
+	// Start pprof listener
+	log.Printf("Starting pprof listener on http://0.0.0.0:%d/debug/pprof\n", memUsageFlags.debugPort)
+	go func() {
+		log.Println(http.ListenAndServe(fmt.Sprintf(":%d", memUsageFlags.debugPort), nil))
+	}()
+
+	for i := 0; i < 10; i++ {
+		showMemoryStats("open")
+
+		conn := createClientConnection(f)
+		errorChan := make(chan error)
+		go func() {
+			for {
+				err, ok := <-errorChan
+				if !ok {
+					return
+				}
+				fmt.Printf("ERROR: %s\n", err)
+				os.Exit(1)
+			}
+		}()
+		o, err := ouroboros.New(
+			ouroboros.WithConnection(conn),
+			ouroboros.WithNetworkMagic(uint32(f.networkMagic)),
+			ouroboros.WithErrorChan(errorChan),
+			ouroboros.WithNodeToNode(f.ntnProto),
+			ouroboros.WithKeepAlive(true),
+		)
+		if err != nil {
+			fmt.Printf("ERROR: %s\n", err)
+			os.Exit(1)
+		}
+		o.ChainSync.Client.Start()
+
+		tip, err := o.ChainSync.Client.GetCurrentTip()
+		if err != nil {
+			fmt.Printf("ERROR: %s\n", err)
+			os.Exit(1)
+		}
+
+		log.Printf("tip: slot = %d, hash = %x\n", tip.Point.Slot, tip.Point.Hash)
+
+		if err := o.Close(); err != nil {
+			fmt.Printf("ERROR: %s\n", err)
+		}
+
+		showMemoryStats("close")
+
+		time.Sleep(5 * time.Second)
+
+		runtime.GC()
+
+		showMemoryStats("after GC")
+	}
+
+	if err := pprof.Lookup("goroutine").WriteTo(os.Stdout, 1); err != nil {
+		fmt.Printf("ERROR: %s\n", err)
+		os.Exit(1)
+	}
+
+	fmt.Printf("waiting forever")
+	select {}
+}
+
+func showMemoryStats(tag string) {
+	var m runtime.MemStats
+	runtime.ReadMemStats(&m)
+	log.Printf("[%s] HeapAlloc: %dKiB\n", tag, m.HeapAlloc/1024)
+}

muxer/muxer.go

@@ -94,7 +94,7 @@ func (m *Muxer) sendError(err error) {
 	m.Stop()
 }
 
-func (m *Muxer) RegisterProtocol(protocolId uint16) (chan *Segment, chan *Segment) {
+func (m *Muxer) RegisterProtocol(protocolId uint16) (chan *Segment, chan *Segment, chan bool) {
 	// Generate channels
 	senderChan := make(chan *Segment, 10)
 	receiverChan := make(chan *Segment, 10)
@@ -118,7 +118,7 @@ func (m *Muxer) RegisterProtocol(protocolId uint16) (chan *Segment, chan *Segmen
 			}
 		}
 	}()
-	return senderChan, receiverChan
+	return senderChan, receiverChan, m.doneChan
 }
 
 func (m *Muxer) Send(msg *Segment) error {

ouroboros.go

@@ -132,20 +132,24 @@ func (o *Ouroboros) setupConnection() error {
 	o.muxer = muxer.New(o.conn)
 	// Start Goroutine to pass along errors from the muxer
 	go func() {
-		err, ok := <-o.muxer.ErrorChan
-		// Break out of goroutine if muxer's error channel is closed
-		if !ok {
+		select {
+		case <-o.doneChan:
 			return
+		case err, ok := <-o.muxer.ErrorChan:
+			// Break out of goroutine if muxer's error channel is closed
+			if !ok {
+				return
+			}
+			if errors.Is(err, io.EOF) || errors.Is(err, io.ErrUnexpectedEOF) {
+				// Return a bare io.EOF error if error is EOF/ErrUnexpectedEOF
+				o.ErrorChan <- io.EOF
+			} else {
+				// Wrap error message to denote it comes from the muxer
+				o.ErrorChan <- fmt.Errorf("muxer error: %s", err)
+			}
+			// Close connection on muxer errors
+			o.Close()
 		}
-		if errors.Is(err, io.EOF) || errors.Is(err, io.ErrUnexpectedEOF) {
-			// Return a bare io.EOF error if error is EOF/ErrUnexpectedEOF
-			o.ErrorChan <- io.EOF
-		} else {
-			// Wrap error message to denote it comes from the muxer
-			o.ErrorChan <- fmt.Errorf("muxer error: %s", err)
-		}
-		// Close connection on muxer errors
-		o.Close()
 	}()
 	protoOptions := protocol.ProtocolOptions{
 		Muxer:     o.muxer,

protocol/chainsync/client.go

@@ -63,6 +63,13 @@ func NewClient(protoOptions protocol.ProtocolOptions, cfg *Config) *Client {
 		InitialState:        STATE_IDLE,
 	}
 	c.Protocol = protocol.New(protoConfig)
+	// Start goroutine to cleanup resources on protocol shutdown
+	go func() {
+		<-c.Protocol.DoneChan()
+		close(c.intersectResultChan)
+		close(c.readyForNextBlockChan)
+		close(c.currentTipChan)
+	}()
 	return c
 }
 

protocol/keepalive/client.go

@@ -40,6 +40,16 @@ func NewClient(protoOptions protocol.ProtocolOptions, cfg *Config) *Client {
 		InitialState:        STATE_CLIENT,
 	}
 	c.Protocol = protocol.New(protoConfig)
+	// Start goroutine to cleanup resources on protocol shutdown
+	go func() {
+		<-c.Protocol.DoneChan()
+		if c.timer != nil {
+			// Stop timer and drain channel
+			if ok := c.timer.Stop(); !ok {
+				<-c.timer.C
+			}
+		}
+	}()
 	return c
 }
 

protocol/localstatequery/client.go

@@ -65,6 +65,12 @@ func NewClient(protoOptions protocol.ProtocolOptions, cfg *Config) *Client {
 		c.enableGetRewardInfoPoolsBlock = true
 	}
 	c.Protocol = protocol.New(protoConfig)
+	// Start goroutine to cleanup resources on protocol shutdown
+	go func() {
+		<-c.Protocol.DoneChan()
+		close(c.queryResultChan)
+		close(c.acquireResultChan)
+	}()
 	return c
 }
 

protocol/localtxsubmission/client.go

@@ -43,6 +43,11 @@ func NewClient(protoOptions protocol.ProtocolOptions, cfg *Config) *Client {
 		InitialState:        STATE_IDLE,
 	}
 	c.Protocol = protocol.New(protoConfig)
+	// Start goroutine to cleanup resources on protocol shutdown
+	go func() {
+		<-c.Protocol.DoneChan()
+		close(c.submitResultChan)
+	}()
 	return c
 }
 

protocol/protocol.go

@@ -22,6 +22,7 @@ type Protocol struct {
 	config               ProtocolConfig
 	muxerSendChan        chan *muxer.Segment
 	muxerRecvChan        chan *muxer.Segment
+	muxerDoneChan        chan bool
 	state                State
 	stateMutex           sync.Mutex
 	recvBuffer           *bytes.Buffer
@@ -77,21 +78,29 @@ type MessageFromCborFunc func(uint, []byte) (Message, error)
 
 func New(config ProtocolConfig) *Protocol {
 	p := &Protocol{
-		config: config,
+		config:   config,
+		doneChan: make(chan bool),
 	}
 	return p
 }
 
 func (p *Protocol) Start() {
 	// Register protocol with muxer
-	p.muxerSendChan, p.muxerRecvChan = p.config.Muxer.RegisterProtocol(p.config.ProtocolId)
+	p.muxerSendChan, p.muxerRecvChan, p.muxerDoneChan = p.config.Muxer.RegisterProtocol(p.config.ProtocolId)
 	// Create buffers and channels
 	p.recvBuffer = bytes.NewBuffer(nil)
 	p.sendQueueChan = make(chan Message, 50)
 	p.sendStateQueueChan = make(chan Message, 50)
 	p.recvReadyChan = make(chan bool, 1)
 	p.sendReadyChan = make(chan bool, 1)
-	p.doneChan = make(chan bool)
+	// Start goroutine to cleanup when shutting down
+	go func() {
+		<-p.doneChan
+		close(p.sendQueueChan)
+		close(p.sendStateQueueChan)
+		close(p.recvReadyChan)
+		close(p.sendReadyChan)
+	}()
 	// Set initial state
 	p.setState(p.config.InitialState)
 	// Start our send and receive Goroutines
@@ -107,6 +116,10 @@ func (p *Protocol) Role() ProtocolRole {
 	return p.config.Role
 }
 
+func (p *Protocol) DoneChan() chan bool {
+	return p.doneChan
+}
+
 func (p *Protocol) SendMessage(msg Message) error {
 	p.sendQueueChan <- msg
 	return nil
@@ -122,14 +135,14 @@ func (p *Protocol) sendLoop() {
 	var err error
 	for {
 		select {
-		case <-p.sendReadyChan:
-			// We are ready to send based on state map
 		case <-p.doneChan:
 			// We are responsible for closing this channel as the sender, even through it
 			// was created by the muxer
 			close(p.muxerSendChan)
 			// Break out of send loop if we're shutting down
 			return
+		case <-p.sendReadyChan:
+			// We are ready to send based on state map
 		}
 		// Lock the state to prevent collisions
 		p.stateMutex.Lock()
@@ -155,7 +168,11 @@ func (p *Protocol) sendLoop() {
 		msgCount := 0
 		for {
 			// Get next message from send queue
-			msg := <-p.sendQueueChan
+			msg, ok := <-p.sendQueueChan
+			if !ok {
+				// We're shutting down
+				return
+			}
 			msgCount = msgCount + 1
 			// Write the message into the send state queue if we already have a new state
 			if setNewState {
@@ -234,20 +251,29 @@ func (p *Protocol) recvLoop() {
 		// Don't grab the next segment from the muxer if we still have data in the buffer
 		if !leftoverData {
 			// Wait for segment
-			segment, ok := <-p.muxerRecvChan
-			// Break out of receive loop if channel is closed
-			if !ok {
+			select {
+			case <-p.muxerDoneChan:
 				close(p.doneChan)
 				return
+			case segment, ok := <-p.muxerRecvChan:
+				if !ok {
+					close(p.doneChan)
+					return
+				}
+				// Add segment payload to buffer
+				p.recvBuffer.Write(segment.Payload)
+				// Save whether it's a response
+				isResponse = segment.IsResponse()
 			}
-			// Add segment payload to buffer
-			p.recvBuffer.Write(segment.Payload)
-			// Save whether it's a response
-			isResponse = segment.IsResponse()
 		}
 		leftoverData = false
 		// Wait until ready to receive based on state map
-		<-p.recvReadyChan
+		select {
+		case <-p.muxerDoneChan:
+			close(p.doneChan)
+			return
+		case <-p.recvReadyChan:
+		}
 		// Decode message into generic list until we can determine what type of message it is.
 		// This also lets us determine how many bytes the message is. We use RawMessage here to
 		// avoid parsing things that we may not be able to parse
@@ -321,6 +347,7 @@ func (p *Protocol) getNewState(msg Message) (State, error) {
 func (p *Protocol) setState(state State) {
 	// Disable any previous state transition timer
 	if p.stateTransitionTimer != nil {
+		// Stop timer and drain channel
 		if !p.stateTransitionTimer.Stop() {
 			<-p.stateTransitionTimer.C
 		}