TODO.md

@@ -33,6 +33,11 @@ tested.
 
 # Completed Steps
 
+- 2026-10-27: once the stop deadline has passed, the AS, peer and peering
+  handlers start no write either. A full batch or a tick of the timer that
+  waited while a write ran past the deadline could still start one. The flush
+  goroutines of the prefix, AS and peer handlers now run the same code (closes
+  #189)
 - 2026-10-27: once the stop deadline has passed, the prefix handler starts no
   flush. A batch that filled while a write ran past the deadline could still be
   written after it (closes #188)

internal/routewatch/app.go

@@ -2,7 +2,9 @@
 // running instance of the application and contains pointers to its core
 // dependencies, and is responsible for initialization. It also contains the
 // ASN WHOIS fetcher for background updates and the database maintainer for
-// background maintenance tasks.
+// background maintenance tasks. The package also holds the handlers that
+// write the feed's updates to the database in batches, and the flush loop
+// that the AS, peer and prefix handlers share.
 package routewatch
 
 import (

internal/routewatch/ashandler.go

@@ -52,7 +52,6 @@ type ASHandler struct {
 	// &mu.
 	batchTaken  sync.Cond
 	batchFullCh chan struct{} // wakes the flush goroutine when batch is full
-	lastFlush   time.Time     // used only by the flush goroutine
 	// stopCh hands Stop's context to the flush goroutine. It holds one, so
 	// Stop does not wait for a write in progress to hand it over.
 	stopCh chan context.Context
@@ -70,19 +69,27 @@ type asnOp struct {
 // Stop when finished to ensure all pending operations are flushed and the
 // background goroutine is terminated.
 func NewASHandler(db database.Store, logger *logger.Logger) *ASHandler {
+	return newASHandler(db, logger, asnBatchTimeout)
+}
+
+// newASHandler is NewASHandler with the flush timer's interval, batchTimeout,
+// in place of asnBatchTimeout. A test that the timer must not disturb gives an
+// interval longer than the test runs.
+func newASHandler(
+	db database.Store, logger *logger.Logger, batchTimeout time.Duration,
+) *ASHandler {
 	h := &ASHandler{
 		db:          db,
 		logger:      logger,
 		batch:       make([]asnOp, 0, asnBatchSize),
 		batchFullCh: make(chan struct{}, 1),
-		lastFlush:   time.Now(),
 		stopCh:      make(chan context.Context, 1),
 		done:        make(chan struct{}),
 	}
 	h.batchTaken.L = &h.mu
 
 	// Start the flush timer goroutine
-	go h.flushLoop()
+	go flushLoop(batchTimeout, h.batchFullCh, h.stopCh, h.done, h.flushBatch)
 
 	return h
 }
@@ -175,33 +182,6 @@ func (h *ASHandler) Stop(ctx context.Context) {
 	}
 }
 
-// flushLoop runs in a goroutine, the only one that writes the batch: it
-// flushes when the batch is full, periodically, and once more on Stop.
-func (h *ASHandler) flushLoop() {
-	defer close(h.done)
-
-	ticker := time.NewTicker(asnBatchTimeout)
-	defer ticker.Stop()
-
-	for {
-		select {
-		case <-ticker.C:
-			if time.Since(h.lastFlush) >= asnBatchTimeout {
-				h.flushBatch()
-			}
-		case <-h.batchFullCh:
-			h.flushBatch()
-		case ctx := <-h.stopCh:
-			// Final flush, unless the stop deadline has passed
-			if ctx.Err() == nil {
-				h.flushBatch()
-			}
-
-			return
-		}
-	}
-}
-
 // takeBatch returns the pending operations and leaves an empty batch in their
 // place for HandleMessage to fill. They count in writing until flushBatch has
 // written them.
@@ -222,11 +202,11 @@ func (h *ASHandler) takeBatch() []asnOp {
 }
 
 // flushBatch takes the pending batch and writes it to the database, without
-// holding the mutex during the write.
-func (h *ASHandler) flushBatch() {
+// holding the mutex during the write. It reports whether there was a batch.
+func (h *ASHandler) flushBatch() bool {
 	batch := h.takeBatch()
 	if len(batch) == 0 {
-		return
+		return false
 	}
 
 	// The earliest and the latest time the batch saw each AS. The batch holds
@@ -250,5 +230,5 @@ func (h *ASHandler) flushBatch() {
 	h.writing = 0
 	h.mu.Unlock()
 
-	h.lastFlush = time.Now()
+	return true
 }

internal/routewatch/batchwrite.go

@@ -0,0 +1,64 @@
+package routewatch
+
+import (
+	"context"
+	"time"
+)
+
+// flushLoop is the flush goroutine of the prefix, AS and peer handlers. It is
+// the only goroutine that writes a handler's batch. flushBatch takes the batch,
+// writes it, and reports whether there was one.
+//
+// flushLoop calls flushBatch when batchFullCh wakes it. It also calls it every
+// batchTimeout, unless it wrote a batch less than batchTimeout ago. When stopCh
+// hands it Stop's context, it calls flushBatch once more, unless the stop
+// deadline has passed. Then it closes done and returns.
+func flushLoop(
+	batchTimeout time.Duration,
+	batchFullCh <-chan struct{},
+	stopCh <-chan context.Context,
+	done chan<- struct{},
+	flushBatch func() bool,
+) {
+	defer close(done)
+
+	ticker := time.NewTicker(batchTimeout)
+	defer ticker.Stop()
+
+	lastFlush := time.Now()
+
+	for {
+		// Stop goes first. A write can run past the stop deadline while a full
+		// batch's wake-up or a tick waits beside Stop's context. The select
+		// below picks one of them at random, but past the deadline no flush
+		// may start.
+		select {
+		case ctx := <-stopCh:
+			// Final flush, unless the stop deadline has passed
+			if ctx.Err() == nil {
+				flushBatch()
+			}
+
+			return
+		default:
+		}
+
+		select {
+		case <-ticker.C:
+			if time.Since(lastFlush) >= batchTimeout && flushBatch() {
+				lastFlush = time.Now()
+			}
+		case <-batchFullCh:
+			if flushBatch() {
+				lastFlush = time.Now()
+			}
+		case ctx := <-stopCh:
+			// Final flush, unless the stop deadline has passed
+			if ctx.Err() == nil {
+				flushBatch()
+			}
+
+			return
+		}
+	}
+}

internal/routewatch/batchwrite_internal_test.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"context"
 	"encoding/json"
+	"fmt"
 	"log/slog"
 	"slices"
 	"sync"
@@ -168,9 +169,10 @@ func returnsInTime(f func()) bool {
 	}
 }
 
-// startBlockedWrite hands h the messages in fill, which fill its batch so that
-// the handler writes it to store, and waits until that write starts. store
-// holds it until the test calls releaseWrites.
+// startBlockedWrite hands h the messages in fill and waits until h starts to
+// write them to store. The prefix, AS and peer handlers start when fill fills
+// their batch, and the peering handler on its timer. store holds the write
+// until the test calls releaseWrites.
 func startBlockedWrite(
 	t *testing.T,
 	store *blockingStore,
@@ -193,7 +195,7 @@ func startBlockedWrite(
 	select {
 	case <-store.writeStarted:
 	case <-time.After(handleMessageTimeout):
-		t.Fatal("the handler did not write its full batch")
+		t.Fatal("the handler did not start to write the messages")
 	}
 }
 
@@ -273,7 +275,7 @@ func handleAtMaxBatchSize(
 }
 
 // stopWhileAWriteIsBlocked starts a blocked write with the messages in fill,
-// hands h the message extra, and stops h with a deadline that passes while
+// hands h the messages in extra, and stops h with a deadline that passes while
 // store holds the write. Stop must return all the same. Then it lets the write
 // finish and waits until done, closed when h's flush goroutine returns. Past
 // the deadline that goroutine skips its last write, so extra is not written,
@@ -287,7 +289,7 @@ func stopWhileAWriteIsBlocked(
 	},
 	done <-chan struct{},
 	fill []*ristypes.RISMessage,
-	extra *ristypes.RISMessage,
+	extra ...*ristypes.RISMessage,
 ) {
 	t.Helper()
 
@@ -296,7 +298,10 @@ func stopWhileAWriteIsBlocked(
 	defer store.releaseWrites()
 
 	startBlockedWrite(t, store, h, fill)
-	h.HandleMessage(extra)
+
+	for _, msg := range extra {
+		h.HandleMessage(msg)
+	}
 
 	ctx, cancel := context.WithTimeout(t.Context(), stopDeadline)
 	defer cancel()
@@ -428,7 +433,7 @@ func TestASHandlerSkipsItsLastWriteAfterTheStopDeadline(t *testing.T) {
 	var logs bytes.Buffer
 
 	store := newBlockingStore()
-	h := NewASHandler(store, newErrorLogger(&logs))
+	h := newASHandler(store, newErrorLogger(&logs), longerThanAnyTest)
 	fill := ristypes.ASPath{Sequence: slices.Repeat([]int{testASNA}, asnBatchSize)}
 	stopWhileAWriteIsBlocked(t, store, h, h.done,
 		[]*ristypes.RISMessage{{Path: fill}},
@@ -447,6 +452,29 @@ func TestASHandlerSkipsItsLastWriteAfterTheStopDeadline(t *testing.T) {
 	}
 }
 
+// TestASHandlerSkipsAFullBatchAfterTheStopDeadline hands the AS handler a full
+// batch while a write is held, so the batch's wake-up of the flush goroutine
+// waits. The stop deadline passes meanwhile. When the write ends, the flush
+// goroutine must stop instead of writing the batch.
+func TestASHandlerSkipsAFullBatchAfterTheStopDeadline(t *testing.T) {
+	t.Parallel()
+
+	store := newBlockingStore()
+	h := newASHandler(store, logger.New(), longerThanAnyTest)
+	fill := ristypes.ASPath{Sequence: slices.Repeat([]int{testASNA}, asnBatchSize)}
+	full := ristypes.ASPath{Sequence: slices.Repeat([]int{testASNB}, asnBatchSize)}
+	stopWhileAWriteIsBlocked(t, store, h, h.done,
+		[]*ristypes.RISMessage{{Path: fill}},
+		&ristypes.RISMessage{Path: full})
+
+	store.mu.Lock()
+	defer store.mu.Unlock()
+
+	if store.asns[testASNB] {
+		t.Errorf("AS%d was written after the stop deadline", testASNB)
+	}
+}
+
 func TestPeerHandlerSkipsItsLastWriteAfterTheStopDeadline(t *testing.T) {
 	t.Parallel()
 
@@ -455,7 +483,7 @@ func TestPeerHandlerSkipsItsLastWriteAfterTheStopDeadline(t *testing.T) {
 	var logs bytes.Buffer
 
 	store := newBlockingStore()
-	h := NewPeerHandler(store, newErrorLogger(&logs))
+	h := newPeerHandler(store, newErrorLogger(&logs), longerThanAnyTest)
 	stopWhileAWriteIsBlocked(t, store, h, h.done,
 		slices.Repeat([]*ristypes.RISMessage{{Peer: testPeerIP}}, peerBatchSize),
 		&ristypes.RISMessage{Peer: otherPeerIP})
@@ -473,6 +501,30 @@ func TestPeerHandlerSkipsItsLastWriteAfterTheStopDeadline(t *testing.T) {
 	}
 }
 
+// TestPeerHandlerSkipsAFullBatchAfterTheStopDeadline hands the peer handler a
+// full batch while a write is held, so the batch's wake-up of the flush
+// goroutine waits. The stop deadline passes meanwhile. When the write ends, the
+// flush goroutine must stop instead of writing the batch.
+func TestPeerHandlerSkipsAFullBatchAfterTheStopDeadline(t *testing.T) {
+	t.Parallel()
+
+	const otherPeerIP = "2001:db8:ffff::2"
+
+	store := newBlockingStore()
+	h := newPeerHandler(store, logger.New(), longerThanAnyTest)
+	stopWhileAWriteIsBlocked(t, store, h, h.done,
+		slices.Repeat([]*ristypes.RISMessage{{Peer: testPeerIP}}, peerBatchSize),
+		slices.Repeat([]*ristypes.RISMessage{{Peer: otherPeerIP}},
+			peerBatchSize)...)
+
+	store.mu.Lock()
+	defer store.mu.Unlock()
+
+	if store.peers[otherPeerIP] {
+		t.Errorf("peer %s was written after the stop deadline", otherPeerIP)
+	}
+}
+
 // TestPeeringHandlerStopCountsTheWriteInProgress hands a running peering
 // handler one AS path and stops it with a deadline that passes while store
 // holds Stop's last write, of that path's peering. Stop must log that path as
@@ -512,6 +564,35 @@ func TestPeeringHandlerStopCountsTheWriteInProgress(t *testing.T) {
 	}
 }
 
+// TestPeeringHandlerStartsNoWriteAfterTheStopDeadline has the peering handler's
+// timer start a write that store holds, and hands the handler one more AS path
+// meanwhile. The stop deadline passes, and a tick of the timer waits. When the
+// write ends, the processing goroutine must stop instead of writing the path.
+func TestPeeringHandlerStartsNoWriteAfterTheStopDeadline(t *testing.T) {
+	t.Parallel()
+
+	// The timer fires many times while Stop waits for its deadline.
+	const processInterval = 10 * time.Millisecond
+
+	store := newBlockingStore()
+	h := newPeeringHandler(store, logger.New(), processInterval)
+	stopWhileAWriteIsBlocked(t, store, h, h.done,
+		[]*ristypes.RISMessage{
+			{Path: ristypes.ASPath{Sequence: []int{testASNA, testASNB}}},
+		},
+		&ristypes.RISMessage{
+			Path: ristypes.ASPath{Sequence: []int{testASNC, testASND}},
+		})
+
+	store.mockStore.mu.Lock()
+	defer store.mockStore.mu.Unlock()
+
+	if store.Peerings[fmt.Sprintf("%d_%d", testASNC, testASND)] {
+		t.Errorf("the peering of AS%d and AS%d was written after the stop "+
+			"deadline", testASNC, testASND)
+	}
+}
+
 // prefixAnnouncement returns a message in which testPeerIP announces prefixes
 // with origin AS testASNA.
 func prefixAnnouncement(prefixes []string) *ristypes.RISMessage {
@@ -549,7 +630,7 @@ func TestASHandlerHandlesMessagesWhileAWriteIsBlocked(t *testing.T) {
 	t.Parallel()
 
 	store := newBlockingStore()
-	h := NewASHandler(store, logger.New())
+	h := newASHandler(store, logger.New(), longerThanAnyTest)
 	fill := ristypes.ASPath{Sequence: slices.Repeat([]int{testASNA}, asnBatchSize)}
 	handleWhileAWriteIsBlocked(t, store, h,
 		[]*ristypes.RISMessage{{Path: fill}},
@@ -570,7 +651,7 @@ func TestPeerHandlerHandlesMessagesWhileAWriteIsBlocked(t *testing.T) {
 	const otherPeerIP = "2001:db8:ffff::2"
 
 	store := newBlockingStore()
-	h := NewPeerHandler(store, logger.New())
+	h := newPeerHandler(store, logger.New(), longerThanAnyTest)
 	handleWhileAWriteIsBlocked(t, store, h,
 		slices.Repeat([]*ristypes.RISMessage{{Peer: testPeerIP}}, peerBatchSize),
 		&ristypes.RISMessage{Peer: otherPeerIP})
@@ -611,7 +692,7 @@ func TestASHandlerWaitsAtTheMaximumBatchSize(t *testing.T) {
 	t.Parallel()
 
 	store := newBlockingStore()
-	h := NewASHandler(store, logger.New())
+	h := newASHandler(store, logger.New(), longerThanAnyTest)
 	fill := ristypes.ASPath{Sequence: slices.Repeat([]int{testASNA}, asnBatchSize)}
 	toMax := ristypes.ASPath{Sequence: slices.Repeat([]int{testASNA}, asnBatchMaxSize)}
 	handleAtMaxBatchSize(t, store, h,
@@ -628,13 +709,17 @@ func TestASHandlerWaitsAtTheMaximumBatchSize(t *testing.T) {
 	}
 }
 
+// TestPeerHandlerWaitsAtTheMaximumBatchSize must not have its flush timer fire.
+// A timer flush during the fill would take only part of it. The batch would
+// then reach its maximum size before the test's last message, and the test
+// would hang.
 func TestPeerHandlerWaitsAtTheMaximumBatchSize(t *testing.T) {
 	t.Parallel()
 
 	const otherPeerIP = "2001:db8:ffff::2"
 
 	store := newBlockingStore()
-	h := NewPeerHandler(store, logger.New())
+	h := newPeerHandler(store, logger.New(), longerThanAnyTest)
 	message := []*ristypes.RISMessage{{Peer: testPeerIP}}
 	handleAtMaxBatchSize(t, store, h,
 		slices.Repeat(message, peerBatchSize),

internal/routewatch/peerhandler.go

@@ -56,7 +56,6 @@ type PeerHandler struct {
 	// is &mu.
 	batchTaken  sync.Cond
 	batchFullCh chan struct{} // wakes the flush goroutine when peerBatch is full
-	lastFlush   time.Time     // used only by the flush goroutine
 	// stopCh hands Stop's context to the flush goroutine. It holds one, so
 	// Stop does not wait for a write in progress to hand it over.
 	stopCh chan context.Context
@@ -75,19 +74,27 @@ type peerUpdate struct {
 // periodically flushes accumulated peer updates to the database. The handler
 // should be stopped by calling Stop when it is no longer needed.
 func NewPeerHandler(db database.Store, logger *logger.Logger) *PeerHandler {
+	return newPeerHandler(db, logger, peerBatchTimeout)
+}
+
+// newPeerHandler is NewPeerHandler with the flush timer's interval,
+// batchTimeout, in place of peerBatchTimeout. A test that the timer must not
+// disturb gives an interval longer than the test runs.
+func newPeerHandler(
+	db database.Store, logger *logger.Logger, batchTimeout time.Duration,
+) *PeerHandler {
 	h := &PeerHandler{
 		db:          db,
 		logger:      logger,
 		peerBatch:   make([]peerUpdate, 0, peerBatchSize),
 		batchFullCh: make(chan struct{}, 1),
-		lastFlush:   time.Now(),
 		stopCh:      make(chan context.Context, 1),
 		done:        make(chan struct{}),
 	}
 	h.batchTaken.L = &h.mu
 
 	// Start the flush timer goroutine
-	go h.flushLoop()
+	go flushLoop(batchTimeout, h.batchFullCh, h.stopCh, h.done, h.flushBatch)
 
 	return h
 }
@@ -173,33 +180,6 @@ func (h *PeerHandler) Stop(ctx context.Context) {
 	}
 }
 
-// flushLoop runs in a goroutine, the only one that writes the batch: it
-// flushes when the batch is full, periodically, and once more on Stop.
-func (h *PeerHandler) flushLoop() {
-	defer close(h.done)
-
-	ticker := time.NewTicker(peerBatchTimeout)
-	defer ticker.Stop()
-
-	for {
-		select {
-		case <-ticker.C:
-			if time.Since(h.lastFlush) >= peerBatchTimeout {
-				h.flushBatch()
-			}
-		case <-h.batchFullCh:
-			h.flushBatch()
-		case ctx := <-h.stopCh:
-			// Final flush, unless the stop deadline has passed
-			if ctx.Err() == nil {
-				h.flushBatch()
-			}
-
-			return
-		}
-	}
-}
-
 // takeBatch returns the pending updates and leaves an empty batch in their
 // place for HandleMessage to fill. They count in writing until flushBatch has
 // written them.
@@ -220,11 +200,11 @@ func (h *PeerHandler) takeBatch() []peerUpdate {
 }
 
 // flushBatch takes the pending batch and writes it to the database, without
-// holding the mutex during the write.
-func (h *PeerHandler) flushBatch() {
+// holding the mutex during the write. It reports whether there was a batch.
+func (h *PeerHandler) flushBatch() bool {
 	batch := h.takeBatch()
 	if len(batch) == 0 {
-		return
+		return false
 	}
 
 	// The earliest and the latest time the batch saw each peer, with the peer
@@ -255,5 +235,5 @@ func (h *PeerHandler) flushBatch() {
 	h.writing = 0
 	h.mu.Unlock()
 
-	h.lastFlush = time.Now()
+	return true
 }

internal/routewatch/peeringhandler.go

@@ -62,6 +62,15 @@ type PeeringHandler struct {
 // periodically processes accumulated AS paths into peering records. The
 // handler begins processing immediately upon creation.
 func NewPeeringHandler(db database.Store, logger *logger.Logger) *PeeringHandler {
+	return newPeeringHandler(db, logger, peeringProcessInterval)
+}
+
+// newPeeringHandler is NewPeeringHandler with the processing timer's interval,
+// processInterval, in place of peeringProcessInterval. A test gives a short
+// one to have the timer start a write.
+func newPeeringHandler(
+	db database.Store, logger *logger.Logger, processInterval time.Duration,
+) *PeeringHandler {
 	h := &PeeringHandler{
 		db:      db,
 		logger:  logger,
@@ -71,7 +80,7 @@ func NewPeeringHandler(db database.Store, logger *logger.Logger) *PeeringHandler
 	}
 
 	// Start the periodic processing goroutine
-	go h.processLoop()
+	go h.processLoop(processInterval)
 
 	return h
 }
@@ -163,15 +172,29 @@ func (h *PeeringHandler) Stop(ctx context.Context) {
 	}
 }
 
-// processLoop runs periodically to process AS paths into peerings, and once
+// processLoop processes AS paths into peerings every processInterval, and once
 // more on Stop.
-func (h *PeeringHandler) processLoop() {
+func (h *PeeringHandler) processLoop(processInterval time.Duration) {
 	defer close(h.done)
 
-	ticker := time.NewTicker(peeringProcessInterval)
+	ticker := time.NewTicker(processInterval)
 	defer ticker.Stop()
 
 	for {
+		// Stop goes first. A write can run past the stop deadline while a
+		// tick waits beside Stop's context. The select below picks one of
+		// them at random, but past the deadline no write may start.
+		select {
+		case ctx := <-h.stopCh:
+			// Final processing, unless the stop deadline has passed
+			if ctx.Err() == nil {
+				h.processPeerings()
+			}
+
+			return
+		default:
+		}
+
 		select {
 		case <-ticker.C:
 			h.processPeerings()

internal/routewatch/prefixhandler.go

@@ -96,7 +96,6 @@ type PrefixHandler struct {
 	// &mu.
 	batchTaken  sync.Cond
 	batchFullCh chan struct{} // wakes the flush goroutine when batch is full
-	lastFlush   time.Time     // used only by the flush goroutine
 	// stopCh hands Stop's context to the flush goroutine. It holds one, so
 	// Stop does not wait for a write in progress to hand it over.
 	stopCh chan context.Context
@@ -147,14 +146,13 @@ func newPrefixHandler(
 		table:       table,
 		batch:       make([]prefixUpdate, 0, prefixBatchSize),
 		batchFullCh: make(chan struct{}, 1),
-		lastFlush:   time.Now(),
 		stopCh:      make(chan context.Context, 1),
 		done:        make(chan struct{}),
 	}
 	h.batchTaken.L = &h.mu
 
 	// Start the flush timer goroutine
-	go h.flushLoop(batchTimeout)
+	go flushLoop(batchTimeout, h.batchFullCh, h.stopCh, h.done, h.flushBatch)
 
 	return h
 }
@@ -324,48 +322,6 @@ func (h *PrefixHandler) peerSessionDown(peer string) {
 	}
 }
 
-// flushLoop runs in a goroutine, the only one that writes the batch: it
-// flushes when the batch is full, every batchTimeout, and once more on Stop.
-func (h *PrefixHandler) flushLoop(batchTimeout time.Duration) {
-	defer close(h.done)
-
-	ticker := time.NewTicker(batchTimeout)
-	defer ticker.Stop()
-
-	for {
-		// Stop goes first. A write can run past the stop deadline while a full
-		// batch's wake-up or a tick waits beside Stop's context. The select
-		// below picks one of them at random, but past the deadline no flush
-		// may start.
-		select {
-		case ctx := <-h.stopCh:
-			// Final flush, unless the stop deadline has passed
-			if ctx.Err() == nil {
-				h.flushBatch()
-			}
-
-			return
-		default:
-		}
-
-		select {
-		case <-ticker.C:
-			if time.Since(h.lastFlush) >= batchTimeout {
-				h.flushBatch()
-			}
-		case <-h.batchFullCh:
-			h.flushBatch()
-		case ctx := <-h.stopCh:
-			// Final flush, unless the stop deadline has passed
-			if ctx.Err() == nil {
-				h.flushBatch()
-			}
-
-			return
-		}
-	}
-}
-
 // takeBatch returns the pending updates, the held ones first, and the peers in
 // peersDown, and leaves an empty batch, no held updates and no peers in their
 // place for HandleMessage to fill. The updates count in writing until
@@ -396,12 +352,13 @@ func (h *PrefixHandler) takeBatch() ([]prefixUpdate, []string) {
 
 // flushBatch writes the routing table's changes, then takes the pending batch
 // and writes it to the database, without holding the mutex during the writes.
-func (h *PrefixHandler) flushBatch() {
+// It reports whether there was a batch, or a peer down to delete the routes of.
+func (h *PrefixHandler) flushBatch() bool {
 	h.writeTableChanges()
 
 	batch, peersDown := h.takeBatch()
 	if len(batch) == 0 && len(peersDown) == 0 {
-		return
+		return false
 	}
 
 	startTime := time.Now()
@@ -485,7 +442,7 @@ func (h *PrefixHandler) flushBatch() {
 		"duration_ms", elapsed.Milliseconds(),
 	)
 
-	h.lastFlush = time.Now()
+	return true
 }
 
 // applyToTable applies update to the routing table in memory: as an

internal/routewatch/prefixhandler_internal_test.go

@@ -981,8 +981,8 @@ func TestPrefixHandlerStopLogsNothingAfterADeleteThatSucceeds(t *testing.T) {
 }
 
 // longerThanAnyTest is a flush timer interval that no test lasts. A test whose
-// prefix handler must flush only when its batch is full and on Stop gives it to
-// newPrefixHandler.
+// prefix, AS or peer handler must flush only when its batch is full and on Stop
+// gives it to newPrefixHandler, newASHandler or newPeerHandler.
 const longerThanAnyTest = time.Hour
 
 // prefixHandlerWithoutTimer returns a prefix handler that writes to store and