Store a new prefix's earliest timestamp as first_seen (closes #112)

A batch's prefix times were taken from each peer's last update for the
prefix, and the latest of those was kept. The prefix tables hold only
first_seen, written when the prefix is new, so a prefix announced by
two peers seconds apart in one batch was stored first seen at the
later time, and the IP lookup could answer with a first_seen after the
route's last_seen. The flush now keeps, for each prefix, the earliest
timestamp among all of the batch's updates for it.

Model: opus-5-5

internal/database/counts_internal_test.go

@@ -148,9 +148,7 @@ func TestLiveCountsTrackWritesInRealtime(t *testing.T) {
 func writeASNsPrefixesAndPeers(t *testing.T, db *Database, ts time.Time) {
 	t.Helper()
 
-	seen := SeenTimes{First: ts, Last: ts}
-
-	err := db.GetOrCreateASNBatch(map[int]SeenTimes{64500: seen, 64501: seen})
+	err := db.GetOrCreateASNBatch(map[int]time.Time{64500: ts, 64501: ts})
 	if err != nil {
 		t.Fatalf("GetOrCreateASNBatch: %v", err)
 	}
@@ -166,14 +164,14 @@ func writeASNsPrefixesAndPeers(t *testing.T, db *Database, ts time.Time) {
 	err = db.UpdatePeerBatch(map[string]PeerUpdate{
 		testV4PeerIP: {
 			PeerIP: testV4PeerIP, PeerASN: 64500,
-			MessageType: "UPDATE", Seen: seen,
+			MessageType: "UPDATE", Timestamp: ts,
 		},
 	})
 	if err != nil {
 		t.Fatalf("UpdatePeerBatch: %v", err)
 	}
 
-	err = db.RecordPeering(64500, 64501, seen)
+	err = db.RecordPeering(64500, 64501, ts)
 	if err != nil {
 		t.Fatalf("RecordPeering: %v", err)
 	}
@@ -194,10 +192,7 @@ func TestLiveCountsSeededFromDatabaseAtStartup(t *testing.T) {
 
 	ts := time.Date(2026, 1, 2, 3, 4, 5, 0, time.UTC)
 
-	seen := SeenTimes{First: ts, Last: ts}
-
-	err = db.GetOrCreateASNBatch(
-		map[int]SeenTimes{64500: seen, 64501: seen, 64502: seen})
+	err = db.GetOrCreateASNBatch(map[int]time.Time{64500: ts, 64501: ts, 64502: ts})
 	if err != nil {
 		t.Fatalf("GetOrCreateASNBatch: %v", err)
 	}

internal/database/database.go

@@ -903,14 +903,13 @@ func (d *Database) UpdatePrefixesBatch(prefixes map[string]time.Time) error {
 	return nil
 }
 
-// newASN returns a new ASN record first seen at seen.First and last seen at
-// seen.Last, with the handle and description from the AS info lookup when it
-// knows the number.
-func newASN(number int, seen SeenTimes) ASN {
+// newASN returns a new ASN record first and last seen at timestamp, with the
+// handle and description from the AS info lookup when it knows the number.
+func newASN(number int, timestamp time.Time) ASN {
 	asn := ASN{
 		ASN:       number,
-		FirstSeen: seen.First,
-		LastSeen:  seen.Last,
+		FirstSeen: timestamp,
+		LastSeen:  timestamp,
 	}
 
 	// Look up ASN info
@@ -922,12 +921,12 @@ func newASN(number int, seen SeenTimes) ASN {
 	return asn
 }
 
-// upsertASN sets the last_seen time of ASN number to seen.Last with the given
+// upsertASN updates the last_seen time of ASN number with the given
 // statements, inserting the ASN when it is new. It reports whether it inserted
 // it.
 func upsertASN(
 	ctx context.Context, selectStmt, updateStmt, insertStmt *sql.Stmt,
-	number int, seen SeenTimes,
+	number int, timestamp time.Time,
 ) (bool, error) {
 	var (
 		asn                 ASN
@@ -938,7 +937,7 @@ func upsertASN(
 		&description, &asn.FirstSeen, &asn.LastSeen)
 	if err == nil {
 		// ASN exists, update last_seen
-		_, err = updateStmt.ExecContext(ctx, seen.Last, number)
+		_, err = updateStmt.ExecContext(ctx, timestamp, number)
 		if err != nil {
 			return false, fmt.Errorf("failed to update ASN %d: %w", number, err)
 		}
@@ -951,7 +950,7 @@ func upsertASN(
 	}
 
 	// ASN doesn't exist, create it
-	asn = newASN(number, seen)
+	asn = newASN(number, timestamp)
 
 	_, err = insertStmt.ExecContext(ctx, asn.ASN, asn.Handle,
 		asn.Description, asn.FirstSeen, asn.LastSeen)
@@ -963,7 +962,7 @@ func upsertASN(
 }
 
 // GetOrCreateASNBatch creates or updates multiple ASNs in a single transaction
-func (d *Database) GetOrCreateASNBatch(asns map[int]SeenTimes) error {
+func (d *Database) GetOrCreateASNBatch(asns map[int]time.Time) error {
 	if len(asns) == 0 {
 		return nil
 	}
@@ -1005,9 +1004,9 @@ func (d *Database) GetOrCreateASNBatch(asns map[int]SeenTimes) error {
 
 	var newASNs int
 
-	for number, seen := range asns {
+	for number, timestamp := range asns {
 		inserted, err := upsertASN(ctx, selectStmt, updateStmt, insertStmt,
-			number, seen)
+			number, timestamp)
 		if err != nil {
 			return err
 		}
@@ -1076,7 +1075,7 @@ func (d *Database) GetOrCreateASN(number int, timestamp time.Time) (*ASN, error)
 	}
 
 	// ASN doesn't exist, create it with ASN info lookup
-	asn = newASN(number, SeenTimes{First: timestamp, Last: timestamp})
+	asn = newASN(number, timestamp)
 
 	_, err = tx.Exec("INSERT INTO asns "+
 		"(asn, handle, description, first_seen, last_seen) "+
@@ -1183,7 +1182,7 @@ func (d *Database) RecordAnnouncement(announcement *Announcement) error {
 }
 
 // RecordPeering records a peering relationship between two ASNs.
-func (d *Database) RecordPeering(asA, asB int, seen SeenTimes) error {
+func (d *Database) RecordPeering(asA, asB int, timestamp time.Time) error {
 	// Validate ASNs
 	if asA <= 0 || asB <= 0 {
 		return fmt.Errorf("%w: asA=%d, asB=%d", errInvalidASN, asA, asB)
@@ -1219,12 +1218,12 @@ func (d *Database) RecordPeering(asA, asB int, seen SeenTimes) error {
 	if exists {
 		_, err = tx.Exec(
 			"UPDATE peerings SET last_seen = ? WHERE as_a = ? AND as_b = ?",
-			seen.Last, asA, asB)
+			timestamp, asA, asB)
 	} else {
 		_, err = tx.Exec(`
 			INSERT INTO peerings (id, as_a, as_b, first_seen, last_seen)
 			VALUES (?, ?, ?, ?, ?)`,
-			generateUUID().String(), asA, asB, seen.First, seen.Last)
+			generateUUID().String(), asA, asB, timestamp, timestamp)
 	}
 
 	if err != nil {
@@ -1302,11 +1301,11 @@ func (d *Database) UpdatePeerBatch(peers map[string]PeerUpdate) error {
 
 		if exists {
 			_, err = updateStmt.ExecContext(ctx, update.PeerASN,
-				update.Seen.Last, update.MessageType, update.PeerIP)
+				update.Timestamp, update.MessageType, update.PeerIP)
 		} else {
 			_, err = insertStmt.ExecContext(ctx,
 				generateUUID().String(), update.PeerIP, update.PeerASN,
-				update.Seen.First, update.Seen.Last, update.MessageType)
+				update.Timestamp, update.Timestamp, update.MessageType)
 		}
 
 		if err != nil {

internal/database/database_internal_test.go

@@ -615,12 +615,10 @@ func TestBatchWriteDuringCheckpoint(t *testing.T) {
 	})
 
 	ts := time.Now().UTC()
-	seen := SeenTimes{First: ts, Last: ts}
-
 	for i := range contentionIterations {
-		asns := map[int]SeenTimes{
-			i % contendedASNCount:                   seen,
-			(i % contendedASNCount) + asnSecondBand: seen,
+		asns := map[int]time.Time{
+			i % contendedASNCount:                   ts,
+			(i % contendedASNCount) + asnSecondBand: ts,
 		}
 
 		err := db.GetOrCreateASNBatch(asns)
@@ -749,8 +747,7 @@ func TestBatchWriteWaitsForAnalyze(t *testing.T) {
 
 	db, messages := newDatabaseWithLockMessages(t)
 	ctx := context.Background()
-	now := time.Now().UTC()
-	asns := map[int]SeenTimes{lockTestASN: {First: now, Last: now}}
+	asns := map[int]time.Time{lockTestASN: time.Now().UTC()}
 
 	// A stored AS gives ANALYZE a table to analyze and statistics to write.
 	err := db.GetOrCreateASNBatch(asns)
@@ -1666,48 +1663,6 @@ func TestUpdatePrefixesBatchKeepsFirstSeen(t *testing.T) {
 	}
 }
 
-// TestUpdatePeerBatchStoresTheEarliestAndLatestTimesOfANewPeer writes a new
-// peer whose updates span 5 seconds. Its row is first seen at the earliest time
-// and last seen at the latest.
-func TestUpdatePeerBatchStoresTheEarliestAndLatestTimesOfANewPeer(
-	t *testing.T,
-) {
-	t.Parallel()
-
-	db, err := New(&config.Config{StateDir: t.TempDir()}, logger.New())
-	if err != nil {
-		t.Fatalf("failed to create database: %v", err)
-	}
-	defer func() { _ = db.Close() }()
-
-	first := time.Date(2026, 1, 2, 3, 4, 5, 0, time.UTC)
-	last := first.Add(5 * time.Second)
-
-	err = db.UpdatePeerBatch(map[string]PeerUpdate{
-		testPeerIP: {
-			PeerIP: testPeerIP, PeerASN: 64500, MessageType: "UPDATE",
-			Seen: SeenTimes{First: first, Last: last},
-		},
-	})
-	if err != nil {
-		t.Fatalf("UpdatePeerBatch: %v", err)
-	}
-
-	var firstSeen, lastSeen time.Time
-
-	err = db.db.QueryRowContext(t.Context(),
-		"SELECT first_seen, last_seen FROM bgp_peers WHERE peer_ip = ?",
-		testPeerIP).Scan(&firstSeen, &lastSeen)
-	if err != nil {
-		t.Fatalf("reading peer %s: %v", testPeerIP, err)
-	}
-
-	if !firstSeen.Equal(first) || !lastSeen.Equal(last) {
-		t.Errorf("peer %s: first seen %s, last seen %s; want %s, %s",
-			testPeerIP, firstSeen, lastSeen, first, last)
-	}
-}
-
 // TestUpsertLiveRouteBatchWritesInKeyOrder writes new routes of two peers out
 // of key order, the last one a second announcement of the first, and checks
 // that the rows were inserted in key order, peer then prefix (each new row's id

internal/database/interface.go

@@ -34,7 +34,7 @@ type Stats struct {
 type Store interface {
 	// ASN operations
 	GetOrCreateASN(number int, timestamp time.Time) (*ASN, error)
-	GetOrCreateASNBatch(asns map[int]SeenTimes) error
+	GetOrCreateASNBatch(asns map[int]time.Time) error
 
 	// Prefix operations
 	GetOrCreatePrefix(prefix string, timestamp time.Time) (*Prefix, error)
@@ -44,7 +44,7 @@ type Store interface {
 	RecordAnnouncement(announcement *Announcement) error
 
 	// Peering operations
-	RecordPeering(asA, asB int, seen SeenTimes) error
+	RecordPeering(asA, asB int, timestamp time.Time) error
 
 	// Statistics
 	GetStats() (Stats, error)

internal/database/models.go

@@ -122,35 +122,12 @@ type LiveRouteDeletion struct {
 	IPVersion int
 }
 
-// SeenTimes is the earliest and the latest time one batch of updates saw an AS,
-// a peer or a peering. A row the batch adds is stored first seen at First and
-// last seen at Last; a row already stored keeps its first_seen and has its
-// last_seen set to Last.
-type SeenTimes struct {
-	First time.Time
-	Last  time.Time
-}
-
-// Add makes t the earliest time of s when it is earlier than First, and the
-// latest when it is later than Last. The zero SeenTimes holds no time yet, so
-// the first Add sets both.
-func (s *SeenTimes) Add(t time.Time) {
-	if s.First.IsZero() || t.Before(s.First) {
-		s.First = t
-	}
-
-	if s.Last.IsZero() || t.After(s.Last) {
-		s.Last = t
-	}
-}
-
-// PeerUpdate represents parameters for updating a peer. PeerASN and
-// MessageType are those of the peer's latest update.
+// PeerUpdate represents parameters for updating a peer
 type PeerUpdate struct {
 	PeerIP      string
 	PeerASN     int
 	MessageType string
-	Seen        SeenTimes
+	Timestamp   time.Time
 }
 
 // ASNWHOISUpdate contains WHOIS data for updating an ASN record.

internal/routewatch/app_integration_internal_test.go

@@ -152,7 +152,7 @@ func (m *mockStore) RecordAnnouncement(_ *database.Announcement) error {
 }
 
 // RecordPeering mock implementation
-func (m *mockStore) RecordPeering(asA, asB int, _ database.SeenTimes) error {
+func (m *mockStore) RecordPeering(asA, asB int, _ time.Time) error {
 	m.mu.Lock()
 	defer m.mu.Unlock()
 
@@ -396,16 +396,16 @@ func (m *mockStore) DeleteLiveRoutesOfPeer(_ string) (int, error) {
 }
 
 // GetOrCreateASNBatch mock implementation
-func (m *mockStore) GetOrCreateASNBatch(asns map[int]database.SeenTimes) error {
+func (m *mockStore) GetOrCreateASNBatch(asns map[int]time.Time) error {
 	m.mu.Lock()
 	defer m.mu.Unlock()
 
-	for number, seen := range asns {
+	for number, timestamp := range asns {
 		if _, exists := m.ASNs[number]; !exists {
 			m.ASNs[number] = &database.ASN{
 				ASN:       number,
-				FirstSeen: seen.First,
-				LastSeen:  seen.Last,
+				FirstSeen: timestamp,
+				LastSeen:  timestamp,
 			}
 			m.ASNCount++
 		}
@@ -766,9 +766,7 @@ const (
 	callClose      = "close"
 )
 
-func (s *closeOrderStore) GetOrCreateASNBatch(
-	asns map[int]database.SeenTimes,
-) error {
+func (s *closeOrderStore) GetOrCreateASNBatch(asns map[int]time.Time) error {
 	s.record(callWrite)
 
 	return s.Store.GetOrCreateASNBatch(asns)

internal/routewatch/ashandler.go

@@ -229,21 +229,19 @@ func (h *ASHandler) flushBatch() {
 		return
 	}
 
-	// The earliest and the latest time the batch saw each AS. The batch holds
-	// several updates for an AS, from many peers, so a new AS is stored first
-	// seen at the earliest of them and last seen at the latest.
-	asns := make(map[int]database.SeenTimes)
+	// Process ASNs first (deduped)
+	asnMap := make(map[int]time.Time)
 	for _, op := range batch {
-		seen := asns[op.number]
-		seen.Add(op.timestamp)
-		asns[op.number] = seen
+		if existing, ok := asnMap[op.number]; !ok || op.timestamp.After(existing) {
+			asnMap[op.number] = op.timestamp
+		}
 	}
 
 	// Process all ASNs in a single batch transaction
-	err := h.db.GetOrCreateASNBatch(asns)
+	err := h.db.GetOrCreateASNBatch(asnMap)
 	if err != nil {
 		h.logger.Error("Failed to process ASN batch",
-			"error", err, "count", len(asns))
+			"error", err, "count", len(asnMap))
 	}
 
 	h.mu.Lock()

internal/routewatch/ashandler_internal_test.go

@@ -1,44 +0,0 @@
-package routewatch
-
-import (
-	"testing"
-
-	"git.eeqj.de/sneak/routewatch/internal/logger"
-)
-
-// TestASHandlerStoresTheEarliestAndLatestTimesOfANewAS handles two updates
-// whose path carries an AS the database does not hold yet, the second 5
-// seconds after the first, in one batch into a real database. The AS is stored
-// first seen at the time of the first update and last seen at the time of the
-// second.
-func TestASHandlerStoresTheEarliestAndLatestTimesOfANewAS(t *testing.T) {
-	t.Parallel()
-
-	db := newTestDatabase(t)
-
-	// Built without NewASHandler's flush goroutine, so the test flushes itself.
-	h := &ASHandler{db: db, logger: logger.New()}
-
-	first := peerAnnouncement(testPeerIP, testV4Prefix)
-	second := peerAnnouncement(testPeerIP, testV4Prefix)
-	second.ParsedTimestamp = first.ParsedTimestamp.Add(secondUpdateAfter)
-
-	h.HandleMessage(first)
-	h.HandleMessage(second)
-	h.flushBatch()
-
-	asn, _, err := db.GetASDetails(testASNA)
-	if err != nil {
-		t.Fatalf("GetASDetails(%d): %v", testASNA, err)
-	}
-
-	if !asn.FirstSeen.Equal(first.ParsedTimestamp) {
-		t.Errorf("first_seen of AS%d = %s, want %s", testASNA,
-			asn.FirstSeen, first.ParsedTimestamp)
-	}
-
-	if !asn.LastSeen.Equal(second.ParsedTimestamp) {
-		t.Errorf("last_seen of AS%d = %s, want %s", testASNA,
-			asn.LastSeen, second.ParsedTimestamp)
-	}
-}

internal/routewatch/batchwrite_internal_test.go

@@ -66,7 +66,7 @@ func (s *blockingStore) UpsertLiveRouteBatch(routes []*database.LiveRoute) error
 	return nil
 }
 
-func (s *blockingStore) GetOrCreateASNBatch(asns map[int]database.SeenTimes) error {
+func (s *blockingStore) GetOrCreateASNBatch(asns map[int]time.Time) error {
 	s.waitForRelease()
 	s.mu.Lock()
 	defer s.mu.Unlock()
@@ -96,12 +96,10 @@ func (s *blockingStore) DeleteLiveRoutesOfPeer(peerIP string) (int, error) {
 	return s.mockStore.DeleteLiveRoutesOfPeer(peerIP)
 }
 
-func (s *blockingStore) RecordPeering(
-	asA, asB int, seen database.SeenTimes,
-) error {
+func (s *blockingStore) RecordPeering(asA, asB int, ts time.Time) error {
 	s.waitForRelease()
 
-	return s.mockStore.RecordPeering(asA, asB, seen)
+	return s.mockStore.RecordPeering(asA, asB, ts)
 }
 
 func (s *blockingStore) waitForRelease() {

internal/routewatch/peerhandler.go

@@ -37,8 +37,8 @@ const (
 
 // PeerHandler tracks BGP peers from UPDATE messages using batched operations.
 // It maintains a queue of peer updates and periodically flushes them to the database
-// in batches to improve performance. The handler writes one row per peer IP
-// address for each batch, with the earliest and the latest time of its updates.
+// in batches to improve performance. The handler deduplicates peer updates within
+// each batch, keeping only the most recent update for each peer IP address.
 type PeerHandler struct {
 	db     database.Store
 	logger *logger.Logger
@@ -227,28 +227,31 @@ func (h *PeerHandler) flushBatch() {
 		return
 	}
 
-	// The earliest and the latest time the batch saw each peer, with the peer
-	// AS and message type of its latest update. The batch holds several
-	// updates for a peer, so a new peer is stored first seen at the earliest of
-	// them and last seen at the latest.
-	peers := make(map[string]database.PeerUpdate)
+	// Deduplicate by peer IP, keeping the latest update for each peer
+	peerMap := make(map[string]peerUpdate)
 	for _, update := range batch {
-		peer, ok := peers[update.peerIP]
-		if !ok || update.timestamp.After(peer.Seen.Last) {
-			peer.PeerIP = update.peerIP
-			peer.PeerASN = update.peerASN
-			peer.MessageType = update.messageType
+		existing, ok := peerMap[update.peerIP]
+		if !ok || update.timestamp.After(existing.timestamp) {
+			peerMap[update.peerIP] = update
 		}
+	}
 
-		peer.Seen.Add(update.timestamp)
-		peers[update.peerIP] = peer
+	// Convert to database format
+	dbPeerMap := make(map[string]database.PeerUpdate)
+	for peerIP, update := range peerMap {
+		dbPeerMap[peerIP] = database.PeerUpdate{
+			PeerIP:      update.peerIP,
+			PeerASN:     update.peerASN,
+			MessageType: update.messageType,
+			Timestamp:   update.timestamp,
+		}
 	}
 
 	// Process all peers in a single batch transaction
-	err := h.db.UpdatePeerBatch(peers)
+	err := h.db.UpdatePeerBatch(dbPeerMap)
 	if err != nil {
 		h.logger.Error("Failed to process peer batch",
-			"error", err, "count", len(peers))
+			"error", err, "count", len(dbPeerMap))
 	}
 
 	h.mu.Lock()

internal/routewatch/peerhandler_internal_test.go

@@ -1,59 +0,0 @@
-package routewatch
-
-import (
-	"testing"
-
-	"git.eeqj.de/sneak/routewatch/internal/database"
-	"git.eeqj.de/sneak/routewatch/internal/logger"
-)
-
-// peerBatchStore keeps the peers of the last UpdatePeerBatch call. The
-// database has no read of the peer table, so the peer handler's test checks
-// what the handler writes.
-type peerBatchStore struct {
-	*mockStore
-
-	peers map[string]database.PeerUpdate
-}
-
-func (s *peerBatchStore) UpdatePeerBatch(
-	peers map[string]database.PeerUpdate,
-) error {
-	s.peers = peers
-
-	return nil
-}
-
-// TestPeerHandlerWritesTheEarliestAndLatestTimesOfANewPeer handles two updates
-// from one peer, the second 5 seconds after the first, in one batch. The peer
-// handler writes the peer first seen at the time of the first update and last
-// seen at the time of the second.
-func TestPeerHandlerWritesTheEarliestAndLatestTimesOfANewPeer(t *testing.T) {
-	t.Parallel()
-
-	store := &peerBatchStore{mockStore: newMockStore()}
-
-	// Built without NewPeerHandler's flush goroutine, so the test flushes
-	// itself.
-	h := &PeerHandler{db: store, logger: logger.New()}
-
-	first := peerAnnouncement(testPeerIP, testV4Prefix)
-	second := peerAnnouncement(testPeerIP, testV4Prefix)
-	second.ParsedTimestamp = first.ParsedTimestamp.Add(secondUpdateAfter)
-
-	h.HandleMessage(first)
-	h.HandleMessage(second)
-	h.flushBatch()
-
-	seen := store.peers[testPeerIP].Seen
-
-	if !seen.First.Equal(first.ParsedTimestamp) {
-		t.Errorf("first_seen of peer %s = %s, want %s", testPeerIP,
-			seen.First, first.ParsedTimestamp)
-	}
-
-	if !seen.Last.Equal(second.ParsedTimestamp) {
-		t.Errorf("last_seen of peer %s = %s, want %s", testPeerIP,
-			seen.Last, second.ParsedTimestamp)
-	}
-}

internal/routewatch/peeringhandler.go

@@ -42,11 +42,10 @@ type PeeringHandler struct {
 	db     database.Store
 	logger *logger.Logger
 
-	// In-memory AS path tracking: each path, JSON-encoded, with the earliest
-	// and the latest time an update carried it.
+	// In-memory AS path tracking
 	mu           sync.Mutex
-	asPaths      map[string]database.SeenTimes
-	droppedPaths int // paths dropped because the map was full
+	asPaths      map[string]time.Time // key is JSON-encoded AS path
+	droppedPaths int                  // paths dropped because the map was full
 	// writing is how many paths processPeerings took from asPaths and has
 	// not finished writing the peerings of.
 	writing int
@@ -65,7 +64,7 @@ func NewPeeringHandler(db database.Store, logger *logger.Logger) *PeeringHandler
 	h := &PeeringHandler{
 		db:      db,
 		logger:  logger,
-		asPaths: make(map[string]database.SeenTimes),
+		asPaths: make(map[string]time.Time),
 		stopCh:  make(chan context.Context, 1),
 		done:    make(chan struct{}),
 	}
@@ -119,18 +118,16 @@ func (h *PeeringHandler) HandleMessage(msg *ristypes.RISMessage) {
 	key := string(pathJSON)
 
 	h.mu.Lock()
-	defer h.mu.Unlock()
-
-	seen, exists := h.asPaths[key]
-	if !exists && len(h.asPaths) >= maxTrackedPaths {
+	if _, exists := h.asPaths[key]; exists {
+		// Already tracked: refresh its timestamp.
+		h.asPaths[key] = timestamp
+	} else if len(h.asPaths) >= maxTrackedPaths {
 		// Map is full; drop this new path and count it.
 		h.droppedPaths++
-
-		return
+	} else {
+		h.asPaths[key] = timestamp
 	}
-
-	seen.Add(timestamp)
-	h.asPaths[key] = seen
+	h.mu.Unlock()
 }
 
 // ProcessPeeringsNow triggers immediate processing of all accumulated AS
@@ -193,7 +190,7 @@ func (h *PeeringHandler) processPeerings() {
 	// released, so the map never grows past a single interval's traffic.
 	h.mu.Lock()
 	paths := h.asPaths
-	h.asPaths = make(map[string]database.SeenTimes)
+	h.asPaths = make(map[string]time.Time)
 	h.writing = len(paths)
 	dropped := h.droppedPaths
 	h.mu.Unlock()
@@ -207,13 +204,9 @@ func (h *PeeringHandler) processPeerings() {
 		low, high int
 	}
 
-	// The earliest and the latest time an update carried each peering. Several
-	// paths, each carried at several times, can hold a peering, so a new
-	// peering is stored first seen at the earliest of them and last seen at the
-	// latest.
-	peerings := make(map[peeringKey]database.SeenTimes)
+	peerings := make(map[peeringKey]time.Time)
 
-	for pathJSON, pathSeen := range paths {
+	for pathJSON, timestamp := range paths {
 		var path []int
 
 		err := json.Unmarshal([]byte(pathJSON), &path)
@@ -240,11 +233,10 @@ func (h *PeeringHandler) processPeerings() {
 			}
 
 			key := peeringKey{low: low, high: high}
-
-			seen := peerings[key]
-			seen.Add(pathSeen.First)
-			seen.Add(pathSeen.Last)
-			peerings[key] = seen
+			// Update timestamp if this is newer
+			if existing, ok := peerings[key]; !ok || timestamp.After(existing) {
+				peerings[key] = timestamp
+			}
 		}
 	}
 
@@ -252,8 +244,8 @@ func (h *PeeringHandler) processPeerings() {
 	start := time.Now()
 	successCount := 0
 
-	for key, seen := range peerings {
-		err := h.db.RecordPeering(key.low, key.high, seen)
+	for key, ts := range peerings {
+		err := h.db.RecordPeering(key.low, key.high, ts)
 		if err != nil {
 			h.logger.Error("Failed to record peering",
 				"as_a", key.low,

internal/routewatch/peeringhandler_internal_test.go

@@ -31,14 +31,12 @@ type recordingStore struct {
 	calls int
 }
 
-func (r *recordingStore) RecordPeering(
-	asA, asB int, seen database.SeenTimes,
-) error {
+func (r *recordingStore) RecordPeering(asA, asB int, ts time.Time) error {
 	r.mu.Lock()
 	r.calls++
 	r.mu.Unlock()
 
-	return r.mockStore.RecordPeering(asA, asB, seen)
+	return r.mockStore.RecordPeering(asA, asB, ts)
 }
 
 func (r *recordingStore) callCount() int {
@@ -54,7 +52,7 @@ func newTestHandler(db database.Store) *PeeringHandler {
 	return &PeeringHandler{
 		db:      db,
 		logger:  logger.New(),
-		asPaths: make(map[string]database.SeenTimes),
+		asPaths: make(map[string]time.Time),
 	}
 }
 
@@ -222,10 +220,10 @@ func TestPeeringHandlerCapDropsAndCounts(t *testing.T) {
 	existing := pathKey(t, testASNA, testASNB)
 
 	h.mu.Lock()
-	h.asPaths[existing] = database.SeenTimes{First: now, Last: now}
+	h.asPaths[existing] = now
 
 	for i := 0; len(h.asPaths) < maxTrackedPaths; i++ {
-		h.asPaths[strconv.Itoa(i)] = database.SeenTimes{First: now, Last: now}
+		h.asPaths[strconv.Itoa(i)] = now
 	}
 	h.mu.Unlock()
 
@@ -255,53 +253,11 @@ func TestPeeringHandlerCapDropsAndCounts(t *testing.T) {
 	}
 
 	h.mu.Lock()
-	gotSeen := h.asPaths[existing]
+	gotTS := h.asPaths[existing]
 	h.mu.Unlock()
 
-	if !gotSeen.Last.Equal(refreshed) {
-		t.Fatalf("existing path last seen not refreshed: want %v, got %v",
-			refreshed, gotSeen.Last)
-	}
-}
-
-// TestPeeringHandlerStoresTheEarliestAndLatestTimesOfANewPeering handles two
-// updates whose path carries a peering the database does not hold yet, the
-// second 5 seconds after the first, in one run into a real database. The
-// peering is stored first seen at the time of the first update and last seen
-// at the time of the second.
-func TestPeeringHandlerStoresTheEarliestAndLatestTimesOfANewPeering(
-	t *testing.T,
-) {
-	t.Parallel()
-
-	db := newTestDatabase(t)
-	h := newTestHandler(db)
-
-	first := peerAnnouncement(testPeerIP, testV4Prefix)
-	second := peerAnnouncement(testPeerIP, testV4Prefix)
-	second.ParsedTimestamp = first.ParsedTimestamp.Add(secondUpdateAfter)
-
-	h.HandleMessage(first)
-	h.HandleMessage(second)
-	h.ProcessPeeringsNow()
-
-	peers, err := db.GetASPeers(testASNA)
-	if err != nil {
-		t.Fatalf("GetASPeers(%d): %v", testASNA, err)
-	}
-
-	if len(peers) != 1 || peers[0].ASN != testASNB {
-		t.Fatalf("peers of AS%d = %+v, want AS%d alone", testASNA, peers,
-			testASNB)
-	}
-
-	if !peers[0].FirstSeen.Equal(first.ParsedTimestamp) {
-		t.Errorf("first_seen of peering AS%d-AS%d = %s, want %s", testASNA,
-			testASNB, peers[0].FirstSeen, first.ParsedTimestamp)
-	}
-
-	if !peers[0].LastSeen.Equal(second.ParsedTimestamp) {
-		t.Errorf("last_seen of peering AS%d-AS%d = %s, want %s", testASNA,
-			testASNB, peers[0].LastSeen, second.ParsedTimestamp)
+	if !gotTS.Equal(refreshed) {
+		t.Fatalf("existing path timestamp not refreshed: want %v, got %v",
+			refreshed, gotTS)
 	}
 }

internal/routewatch/prefixhandler_internal_test.go

@@ -26,10 +26,6 @@ const (
 	testV6Prefix = "2001:db8:1::/48"
 )
 
-// secondUpdateAfter is how long after the first update the tests of first_seen
-// and last_seen send the second, in the same batch.
-const secondUpdateAfter = 5 * time.Second
-
 // TestPrefixHandlerStoresPrefixesTheIPLookupFinds runs announcements and
 // withdrawals through the prefix handler into a real database and looks the
 // addresses up. The prefixes are written the way the feed sends them: IPv6
@@ -98,7 +94,10 @@ func TestPrefixHandlerStoresANewPrefixFirstSeenAtItsEarliestUpdate(
 ) {
 	t.Parallel()
 
-	const otherPeerIP = "2001:db8:ffff::2"
+	const (
+		otherPeerIP = "2001:db8:ffff::2"
+		secondAfter = 5 * time.Second
+	)
 
 	tests := []struct {
 		name                  string
@@ -114,7 +113,7 @@ func TestPrefixHandlerStoresANewPrefixFirstSeenAtItsEarliestUpdate(
 
 			first := peerAnnouncement(tt.firstPeer, testV4Prefix)
 			second := peerAnnouncement(tt.secondPeer, testV4Prefix)
-			second.ParsedTimestamp = first.ParsedTimestamp.Add(secondUpdateAfter)
+			second.ParsedTimestamp = first.ParsedTimestamp.Add(secondAfter)
 			db := handleBatches(t, [][]*ristypes.RISMessage{{first, second}})
 
 			info, err := db.GetIPInfo("192.0.2.1")