internal/audio/cgo_audio.go

@@ -94,25 +94,28 @@ func cgoAudioInit() error {
 	cache := GetCachedConfig()
 	cache.Update()
 
+	// Enable C trace logging if Go audio scope trace level is active
+
 	// Enable C trace logging if Go audio scope trace level is active
 	audioLogger := logging.GetSubsystemLogger("audio")
 	loggerTraceEnabled := audioLogger.GetLevel() <= zerolog.TraceLevel
 
 	// Manual check for audio scope in PION_LOG_TRACE (workaround for logging system bug)
-	traceEnabled := loggerTraceEnabled
-	if !loggerTraceEnabled {
-		pionTrace := os.Getenv("PION_LOG_TRACE")
-		if pionTrace != "" {
-			scopes := strings.Split(strings.ToLower(pionTrace), ",")
-			for _, scope := range scopes {
-				if strings.TrimSpace(scope) == "audio" {
-					traceEnabled = true
-					break
-				}
+	manualTraceEnabled := false
+	pionTrace := os.Getenv("PION_LOG_TRACE")
+	if pionTrace != "" {
+		scopes := strings.Split(strings.ToLower(pionTrace), ",")
+		for _, scope := range scopes {
+			if strings.TrimSpace(scope) == "audio" {
+				manualTraceEnabled = true
+				break
 			}
 		}
 	}
 
+	// Use manual check as fallback if logging system fails
+	traceEnabled := loggerTraceEnabled || manualTraceEnabled
+
 	CGOSetTraceLogging(traceEnabled)
 
 	// Update C constants from cached config (atomic access, no locks)
@@ -147,17 +150,15 @@ func cgoAudioClose() {
 
 // AudioConfigCache provides a comprehensive caching system for audio configuration
 type AudioConfigCache struct {
-	// All duration fields use int32 by storing as milliseconds for optimal ARM NEON performance
-	maxMetricsUpdateInterval atomic.Int32 // Store as milliseconds (10s = 10K ms < int32 max)
-	restartWindow            atomic.Int32 // Store as milliseconds (5min = 300K ms < int32 max)
-	restartDelay             atomic.Int32 // Store as milliseconds
-	maxRestartDelay          atomic.Int32 // Store as milliseconds
-
-	// Short-duration fields stored as milliseconds with int32
-	minFrameDuration         atomic.Int32 // Store as milliseconds (10ms = 10 ms < int32 max)
-	maxFrameDuration         atomic.Int32 // Store as milliseconds (100ms = 100 ms < int32 max)
-	maxLatency               atomic.Int32 // Store as milliseconds (500ms = 500 ms < int32 max)
-	minMetricsUpdateInterval atomic.Int32 // Store as milliseconds (100ms = 100 ms < int32 max)
+	// Atomic int64 fields MUST be first for ARM32 alignment (8-byte alignment required)
+	minFrameDuration         atomic.Int64 // Store as nanoseconds
+	maxFrameDuration         atomic.Int64 // Store as nanoseconds
+	maxLatency               atomic.Int64 // Store as nanoseconds
+	minMetricsUpdateInterval atomic.Int64 // Store as nanoseconds
+	maxMetricsUpdateInterval atomic.Int64 // Store as nanoseconds
+	restartWindow            atomic.Int64 // Store as nanoseconds
+	restartDelay             atomic.Int64 // Store as nanoseconds
+	maxRestartDelay          atomic.Int64 // Store as nanoseconds
 
 	// Atomic int32 fields for lock-free access to frequently used values
 	minReadEncodeBuffer  atomic.Int32
@@ -245,16 +246,8 @@ func (c *AudioConfigCache) Update() {
 		// Update additional validation values
 		c.maxAudioFrameSize.Store(int32(Config.MaxAudioFrameSize))
 		c.maxChannels.Store(int32(Config.MaxChannels))
-
-		// Store duration fields as milliseconds for int32 optimization
-		c.minFrameDuration.Store(int32(Config.MinFrameDuration / time.Millisecond))
-		c.maxFrameDuration.Store(int32(Config.MaxFrameDuration / time.Millisecond))
-		c.maxLatency.Store(int32(Config.MaxLatency / time.Millisecond))
-		c.minMetricsUpdateInterval.Store(int32(Config.MinMetricsUpdateInterval / time.Millisecond))
-		c.maxMetricsUpdateInterval.Store(int32(Config.MaxMetricsUpdateInterval / time.Millisecond))
-		c.restartWindow.Store(int32(Config.RestartWindow / time.Millisecond))
-		c.restartDelay.Store(int32(Config.RestartDelay / time.Millisecond))
-		c.maxRestartDelay.Store(int32(Config.MaxRestartDelay / time.Millisecond))
+		c.minFrameDuration.Store(int64(Config.MinFrameDuration))
+		c.maxFrameDuration.Store(int64(Config.MaxFrameDuration))
 		c.minOpusBitrate.Store(int32(Config.MinOpusBitrate))
 		c.maxOpusBitrate.Store(int32(Config.MaxOpusBitrate))
 
@@ -305,6 +298,20 @@ func (c *AudioConfigCache) GetBufferTooLargeError() error {
 	return c.bufferTooLargeDecodeWrite
 }
 
+// updateCacheIfNeeded updates cache only if expired to avoid overhead
+func updateCacheIfNeeded(cache *AudioConfigCache) {
+	if cache.initialized.Load() {
+		cache.mutex.RLock()
+		cacheExpired := time.Since(cache.lastUpdate) > cache.cacheExpiry
+		cache.mutex.RUnlock()
+		if cacheExpired {
+			cache.Update()
+		}
+	} else {
+		cache.Update()
+	}
+}
+
 func cgoAudioReadEncode(buf []byte) (int, error) {
 	// Minimal buffer validation - assume caller provides correct size
 	if len(buf) == 0 {
@@ -403,6 +410,7 @@ func cgoAudioDecodeWrite(buf []byte) (int, error) {
 		return n, nil
 	}
 
+	// Error handling with static errors
 	audioDecodeWriteFailures.Add(1)
 	var errMsg string
 	var err error
@@ -472,7 +480,7 @@ func ReturnBufferToPool(buf []byte) {
 // ReadEncodeWithPooledBuffer reads audio data and encodes it using a buffer from the pool
 func ReadEncodeWithPooledBuffer() ([]byte, int, error) {
 	cache := GetCachedConfig()
-	cache.Update()
+	updateCacheIfNeeded(cache)
 
 	bufferSize := cache.GetMinReadEncodeBuffer()
 	if bufferSize == 0 {
@@ -496,7 +504,7 @@ func DecodeWriteWithPooledBuffer(data []byte) (int, error) {
 	}
 
 	cache := GetCachedConfig()
-	cache.Update()
+	updateCacheIfNeeded(cache)
 
 	maxPacketSize := cache.GetMaxPacketSize()
 	if len(data) > maxPacketSize {
@@ -544,7 +552,18 @@ func cgoAudioDecodeWriteWithBuffers(opusData []byte, pcmBuffer []byte) (int, err
 
 	// Get cached config
 	cache := GetCachedConfig()
-	cache.Update()
+	// Only update cache if expired - avoid unnecessary overhead
+	// Use proper locking to avoid race condition
+	if cache.initialized.Load() {
+		cache.mutex.RLock()
+		cacheExpired := time.Since(cache.lastUpdate) > cache.cacheExpiry
+		cache.mutex.RUnlock()
+		if cacheExpired {
+			cache.Update()
+		}
+	} else {
+		cache.Update()
+	}
 
 	// Ensure data doesn't exceed max packet size
 	maxPacketSize := cache.GetMaxPacketSize()
@@ -555,6 +574,8 @@ func cgoAudioDecodeWriteWithBuffers(opusData []byte, pcmBuffer []byte) (int, err
 		return 0, newBufferTooLargeError(len(opusData), maxPacketSize)
 	}
 
+	// Metrics tracking only - detailed logging handled at application level
+
 	// Direct CGO call with minimal overhead - unsafe.Pointer(&slice[0]) is never nil for non-empty slices
 	n := int(C.jetkvm_audio_decode_write(unsafe.Pointer(&opusData[0]), C.int(len(opusData))))
 
@@ -564,6 +585,7 @@ func cgoAudioDecodeWriteWithBuffers(opusData []byte, pcmBuffer []byte) (int, err
 		return n, nil
 	}
 
+	// Handle error cases with static error codes to reduce allocations
 	audioDecodeWriteFailures.Add(1)
 	var errMsg string
 	var err error
@@ -586,6 +608,8 @@ func cgoAudioDecodeWriteWithBuffers(opusData []byte, pcmBuffer []byte) (int, err
 	return 0, err
 }
 
+// Optimized CGO function aliases - use direct function calls to reduce overhead
+// These are now direct function aliases instead of variable assignments
 func CGOAudioInit() error                        { return cgoAudioInit() }
 func CGOAudioClose()                             { cgoAudioClose() }
 func CGOAudioReadEncode(buf []byte) (int, error) { return cgoAudioReadEncode(buf) }

internal/audio/input_microphone_manager.go

@@ -110,6 +110,8 @@ func (aim *AudioInputManager) WriteOpusFrame(frame []byte) error {
 		aim.logger.Warn().
 			Float64("latency_ms", latencyMs).
 			Msg("High audio processing latency detected")
+
+		// Record latency for goroutine cleanup optimization
 	}
 
 	if err != nil {
@@ -146,6 +148,8 @@ func (aim *AudioInputManager) WriteOpusFrameZeroCopy(frame *ZeroCopyAudioFrame)
 		aim.logger.Warn().
 			Float64("latency_ms", latencyMs).
 			Msg("High audio processing latency detected")
+
+		// Record latency for goroutine cleanup optimization
 	}
 
 	if err != nil {

internal/audio/input_supervisor.go

@@ -139,6 +139,8 @@ func (ais *AudioInputSupervisor) startProcess() error {
 	ais.processPID = ais.cmd.Process.Pid
 	ais.logger.Info().Int("pid", ais.processPID).Strs("args", args).Strs("opus_env", ais.opusEnv).Msg("audio input server process started")
 
+	// Add process to monitoring
+
 	// Connect client to the server synchronously to avoid race condition
 	ais.connectClient()
 

serial.go

@@ -3,6 +3,7 @@ package kvm
 import (
 	"bufio"
 	"io"
+	"runtime"
 	"strconv"
 	"strings"
 	"time"
@@ -141,6 +142,10 @@ func unmountDCControl() error {
 var dcState DCPowerState
 
 func runDCControl() {
+	// Lock to OS thread to isolate DC control serial I/O
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	scopedLogger := serialLogger.With().Str("service", "dc_control").Logger()
 	reader := bufio.NewReader(port)
 	hasRestoreFeature := false
@@ -290,6 +295,10 @@ func handleSerialChannel(d *webrtc.DataChannel) {
 
 	d.OnOpen(func() {
 		go func() {
+			// Lock to OS thread to isolate serial I/O
+			runtime.LockOSThread()
+			defer runtime.UnlockOSThread()
+
 			buf := make([]byte, 1024)
 			for {
 				n, err := port.Read(buf)