Try to improve cpu usage

holepunch/tester.go

@@ -41,6 +41,12 @@ func DefaultTestOptions() TestConnectionOptions {
 	}
 }
 
+// cachedAddr holds a cached resolved UDP address
+type cachedAddr struct {
+	addr      *net.UDPAddr
+	resolvedAt time.Time
+}
+
 // HolepunchTester monitors holepunch connectivity using magic packets
 type HolepunchTester struct {
 	sharedBind *bind.SharedBind
@@ -53,6 +59,11 @@ type HolepunchTester struct {
 
 	// Callback when connection status changes
 	callback HolepunchStatusCallback
+
+	// Address cache to avoid repeated DNS/UDP resolution
+	addrCache    map[string]*cachedAddr
+	addrCacheMu  sync.RWMutex
+	addrCacheTTL time.Duration // How long cached addresses are valid
 }
 
 // HolepunchStatus represents the status of a holepunch connection
@@ -76,6 +87,8 @@ type pendingRequest struct {
 func NewHolepunchTester(sharedBind *bind.SharedBind) *HolepunchTester {
 	return &HolepunchTester{
 		sharedBind:   sharedBind,
+		addrCache:    make(map[string]*cachedAddr),
+		addrCacheTTL: 5 * time.Minute, // Cache addresses for 5 minutes
 	}
 }
 
@@ -135,9 +148,67 @@ func (t *HolepunchTester) Stop() {
 		return true
 	})
 
+	// Clear address cache
+	t.addrCacheMu.Lock()
+	t.addrCache = make(map[string]*cachedAddr)
+	t.addrCacheMu.Unlock()
+
 	logger.Debug("HolepunchTester stopped")
 }
 
+// resolveEndpoint resolves an endpoint to a UDP address, using cache when possible
+func (t *HolepunchTester) resolveEndpoint(endpoint string) (*net.UDPAddr, error) {
+	// Check cache first
+	t.addrCacheMu.RLock()
+	cached, ok := t.addrCache[endpoint]
+	ttl := t.addrCacheTTL
+	t.addrCacheMu.RUnlock()
+
+	if ok && time.Since(cached.resolvedAt) < ttl {
+		return cached.addr, nil
+	}
+
+	// Resolve the endpoint
+	host, err := util.ResolveDomain(endpoint)
+	if err != nil {
+		host = endpoint
+	}
+
+	_, _, err = net.SplitHostPort(host)
+	if err != nil {
+		host = net.JoinHostPort(host, "21820")
+	}
+
+	remoteAddr, err := net.ResolveUDPAddr("udp", host)
+	if err != nil {
+		return nil, fmt.Errorf("failed to resolve UDP address %s: %w", host, err)
+	}
+
+	// Cache the result
+	t.addrCacheMu.Lock()
+	t.addrCache[endpoint] = &cachedAddr{
+		addr:       remoteAddr,
+		resolvedAt: time.Now(),
+	}
+	t.addrCacheMu.Unlock()
+
+	return remoteAddr, nil
+}
+
+// InvalidateCache removes a specific endpoint from the address cache
+func (t *HolepunchTester) InvalidateCache(endpoint string) {
+	t.addrCacheMu.Lock()
+	delete(t.addrCache, endpoint)
+	t.addrCacheMu.Unlock()
+}
+
+// ClearCache clears all cached addresses
+func (t *HolepunchTester) ClearCache() {
+	t.addrCacheMu.Lock()
+	t.addrCache = make(map[string]*cachedAddr)
+	t.addrCacheMu.Unlock()
+}
+
 // handleResponse is called by SharedBind when a magic response is received
 func (t *HolepunchTester) handleResponse(addr netip.AddrPort, echoData []byte) {
 	logger.Debug("Received magic response from %s", addr.String())
@@ -183,20 +254,10 @@ func (t *HolepunchTester) TestEndpoint(endpoint string, timeout time.Duration) T
 		return result
 	}
 
-	// Resolve the endpoint
-	host, err := util.ResolveDomain(endpoint)
+	// Resolve the endpoint (using cache)
+	remoteAddr, err := t.resolveEndpoint(endpoint)
 	if err != nil {
-		host = endpoint
-	}
-
-	_, _, err = net.SplitHostPort(host)
-	if err != nil {
-		host = net.JoinHostPort(host, "21820")
-	}
-
-	remoteAddr, err := net.ResolveUDPAddr("udp", host)
-	if err != nil {
-		result.Error = fmt.Errorf("failed to resolve UDP address %s: %w", host, err)
+		result.Error = err
 		return result
 	}