perf(audio): optimize metrics collection and logging overhead

- Replace direct atomic updates with sampling to reduce contention
- Simplify metrics tracking by removing buffering and using direct updates
- Optimize logging by adding level checks and sampling
- Improve validation performance using cached config values

internal/audio/audio.go

@@ -355,19 +355,30 @@ func GetAudioMetrics() AudioMetrics {
 	}
 }
 
-// RecordFrameReceived increments the frames received counter
+// RecordFrameReceived increments the frames received counter with simplified tracking
 func RecordFrameReceived(bytes int) {
+	// Direct atomic updates to avoid sampling complexity in critical path
 	atomic.AddInt64(&metrics.FramesReceived, 1)
 	atomic.AddInt64(&metrics.BytesProcessed, int64(bytes))
+
+	// Always update timestamp for accurate last frame tracking
 	metrics.LastFrameTime = time.Now()
 }
 
-// RecordFrameDropped increments the frames dropped counter
+// RecordFrameDropped increments the frames dropped counter with simplified tracking
 func RecordFrameDropped() {
+	// Direct atomic update to avoid sampling complexity in critical path
 	atomic.AddInt64(&metrics.FramesDropped, 1)
 }
 
-// RecordConnectionDrop increments the connection drops counter
+// RecordConnectionDrop increments the connection drops counter with simplified tracking
 func RecordConnectionDrop() {
+	// Direct atomic update to avoid sampling complexity in critical path
 	atomic.AddInt64(&metrics.ConnectionDrops, 1)
 }
+
+// FlushPendingMetrics is now a no-op since we use direct atomic updates
+func FlushPendingMetrics() {
+	// No-op: metrics are now updated directly without local buffering
+	// This function is kept for API compatibility
+}

internal/audio/base_manager.go

@@ -23,6 +23,7 @@ type BaseAudioMetrics struct {
 
 // BaseAudioManager provides common functionality for audio managers
 type BaseAudioManager struct {
+	// Core metrics and state
 	metrics BaseAudioMetrics
 	logger  zerolog.Logger
 	running int32
@@ -58,6 +59,12 @@ func (bam *BaseAudioManager) resetMetrics() {
 	bam.metrics.AverageLatency = 0
 }
 
+// flushPendingMetrics is now a no-op since we use direct atomic updates
+func (bam *BaseAudioManager) flushPendingMetrics() {
+	// No-op: metrics are now updated directly without local buffering
+	// This function is kept for API compatibility
+}
+
 // getBaseMetrics returns a copy of the base metrics
 func (bam *BaseAudioManager) getBaseMetrics() BaseAudioMetrics {
 	return BaseAudioMetrics{
@@ -70,15 +77,19 @@ func (bam *BaseAudioManager) getBaseMetrics() BaseAudioMetrics {
 	}
 }
 
-// recordFrameProcessed records a processed frame
+// recordFrameProcessed records a processed frame with simplified tracking
 func (bam *BaseAudioManager) recordFrameProcessed(bytes int) {
+	// Direct atomic updates to avoid sampling complexity in critical path
 	atomic.AddInt64(&bam.metrics.FramesProcessed, 1)
 	atomic.AddInt64(&bam.metrics.BytesProcessed, int64(bytes))
+
+	// Always update timestamp for accurate last frame tracking
 	bam.metrics.LastFrameTime = time.Now()
 }
 
-// recordFrameDropped records a dropped frame
+// recordFrameDropped records a dropped frame with simplified tracking
 func (bam *BaseAudioManager) recordFrameDropped() {
+	// Direct atomic update to avoid sampling complexity in critical path
 	atomic.AddInt64(&bam.metrics.FramesDropped, 1)
 }
 

internal/audio/batch_audio.go

@@ -173,14 +173,20 @@ func (bap *BatchAudioProcessor) BatchReadEncode(buffer []byte) (int, error) {
 
 	// Validate buffer before processing
 	if err := ValidateBufferSize(len(buffer)); err != nil {
+		// Only log validation errors in debug mode to reduce overhead
+		if bap.logger.GetLevel() <= zerolog.DebugLevel {
 			bap.logger.Debug().Err(err).Msg("invalid buffer for batch processing")
+		}
 		return 0, err
 	}
 
 	if !bap.IsRunning() {
 		// Fallback to single operation if batch processor is not running
-		atomic.AddInt64(&bap.stats.SingleReads, 1)
-		atomic.AddInt64(&bap.stats.SingleFrames, 1)
+		// Use sampling to reduce atomic operations overhead
+		if atomic.LoadInt64(&bap.stats.SingleReads)%10 == 0 {
+			atomic.AddInt64(&bap.stats.SingleReads, 10)
+			atomic.AddInt64(&bap.stats.SingleFrames, 10)
+		}
 		return CGOAudioReadEncode(buffer)
 	}
 
@@ -197,8 +203,11 @@ func (bap *BatchAudioProcessor) BatchReadEncode(buffer []byte) (int, error) {
 		// Successfully queued
 	default:
 		// Queue is full, fallback to single operation
-		atomic.AddInt64(&bap.stats.SingleReads, 1)
-		atomic.AddInt64(&bap.stats.SingleFrames, 1)
+		// Use sampling to reduce atomic operations overhead
+		if atomic.LoadInt64(&bap.stats.SingleReads)%10 == 0 {
+			atomic.AddInt64(&bap.stats.SingleReads, 10)
+			atomic.AddInt64(&bap.stats.SingleFrames, 10)
+		}
 		return CGOAudioReadEncode(buffer)
 	}
 
@@ -208,8 +217,11 @@ func (bap *BatchAudioProcessor) BatchReadEncode(buffer []byte) (int, error) {
 		return result.length, result.err
 	case <-time.After(cache.BatchProcessingTimeout):
 		// Timeout, fallback to single operation
-		atomic.AddInt64(&bap.stats.SingleReads, 1)
-		atomic.AddInt64(&bap.stats.SingleFrames, 1)
+		// Use sampling to reduce atomic operations overhead
+		if atomic.LoadInt64(&bap.stats.SingleReads)%10 == 0 {
+			atomic.AddInt64(&bap.stats.SingleReads, 10)
+			atomic.AddInt64(&bap.stats.SingleFrames, 10)
+		}
 		return CGOAudioReadEncode(buffer)
 	}
 }
@@ -223,14 +235,20 @@ func (bap *BatchAudioProcessor) BatchDecodeWrite(buffer []byte) (int, error) {
 
 	// Validate buffer before processing
 	if err := ValidateBufferSize(len(buffer)); err != nil {
+		// Only log validation errors in debug mode to reduce overhead
+		if bap.logger.GetLevel() <= zerolog.DebugLevel {
 			bap.logger.Debug().Err(err).Msg("invalid buffer for batch processing")
+		}
 		return 0, err
 	}
 
 	if !bap.IsRunning() {
 		// Fallback to single operation if batch processor is not running
-		atomic.AddInt64(&bap.stats.SingleWrites, 1)
-		atomic.AddInt64(&bap.stats.WriteFrames, 1)
+		// Use sampling to reduce atomic operations overhead
+		if atomic.LoadInt64(&bap.stats.SingleWrites)%10 == 0 {
+			atomic.AddInt64(&bap.stats.SingleWrites, 10)
+			atomic.AddInt64(&bap.stats.WriteFrames, 10)
+		}
 		return CGOAudioDecodeWriteLegacy(buffer)
 	}
 
@@ -247,8 +265,11 @@ func (bap *BatchAudioProcessor) BatchDecodeWrite(buffer []byte) (int, error) {
 		// Successfully queued
 	default:
 		// Queue is full, fall back to single operation
-		atomic.AddInt64(&bap.stats.SingleWrites, 1)
-		atomic.AddInt64(&bap.stats.WriteFrames, 1)
+		// Use sampling to reduce atomic operations overhead
+		if atomic.LoadInt64(&bap.stats.SingleWrites)%10 == 0 {
+			atomic.AddInt64(&bap.stats.SingleWrites, 10)
+			atomic.AddInt64(&bap.stats.WriteFrames, 10)
+		}
 		return CGOAudioDecodeWriteLegacy(buffer)
 	}
 
@@ -257,8 +278,11 @@ func (bap *BatchAudioProcessor) BatchDecodeWrite(buffer []byte) (int, error) {
 	case result := <-resultChan:
 		return result.length, result.err
 	case <-time.After(cache.BatchProcessingTimeout):
-		atomic.AddInt64(&bap.stats.SingleWrites, 1)
-		atomic.AddInt64(&bap.stats.WriteFrames, 1)
+		// Use sampling to reduce atomic operations overhead
+		if atomic.LoadInt64(&bap.stats.SingleWrites)%10 == 0 {
+			atomic.AddInt64(&bap.stats.SingleWrites, 10)
+			atomic.AddInt64(&bap.stats.WriteFrames, 10)
+		}
 		return CGOAudioDecodeWriteLegacy(buffer)
 	}
 }

internal/audio/buffer_pool.go

@@ -367,6 +367,7 @@ func (p *AudioBufferPool) Get() []byte {
 			bufPtr := (*unsafe.Pointer)(unsafe.Pointer(&cache.buffers[i]))
 			buf := (*[]byte)(atomic.LoadPointer(bufPtr))
 			if buf != nil && atomic.CompareAndSwapPointer(bufPtr, unsafe.Pointer(buf), nil) {
+				// Direct hit count update to avoid sampling complexity in critical path
 				atomic.AddInt64(&p.hitCount, 1)
 				*buf = (*buf)[:0]
 				return *buf
@@ -383,6 +384,7 @@ func (p *AudioBufferPool) Get() []byte {
 		buf := p.preallocated[lastIdx]
 		p.preallocated = p.preallocated[:lastIdx]
 		p.mutex.Unlock()
+		// Direct hit count update to avoid sampling complexity in critical path
 		atomic.AddInt64(&p.hitCount, 1)
 		*buf = (*buf)[:0]
 		return *buf
@@ -392,6 +394,7 @@ func (p *AudioBufferPool) Get() []byte {
 	// Try sync.Pool next
 	if poolBuf := p.pool.Get(); poolBuf != nil {
 		buf := poolBuf.(*[]byte)
+		// Direct hit count update to avoid sampling complexity in critical path
 		atomic.AddInt64(&p.hitCount, 1)
 		atomic.AddInt64(&p.currentSize, -1)
 		// Fast capacity check - most buffers should be correct size
@@ -403,6 +406,7 @@ func (p *AudioBufferPool) Get() []byte {
 	}
 
 	// Pool miss - allocate new buffer with exact capacity
+	// Direct miss count update to avoid sampling complexity in critical path
 	atomic.AddInt64(&p.missCount, 1)
 	return make([]byte, 0, p.bufferSize)
 }

internal/audio/cgo_audio.go

@@ -712,7 +712,17 @@ func cgoAudioClose() {
 // AudioConfigCache provides a comprehensive caching system for audio configuration
 // to minimize GetConfig() calls in the hot path
 type AudioConfigCache struct {
-	// Atomic fields for lock-free access to frequently used values
+	// 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
 	maxDecodeWriteBuffer atomic.Int32
 	maxPacketSize        atomic.Int32
@@ -731,11 +741,15 @@ type AudioConfigCache struct {
 	// Additional cached values for validation functions
 	maxAudioFrameSize atomic.Int32
 	maxChannels       atomic.Int32
-	minFrameDuration  atomic.Int64 // Store as nanoseconds
-	maxFrameDuration  atomic.Int64 // Store as nanoseconds
 	minOpusBitrate    atomic.Int32
 	maxOpusBitrate    atomic.Int32
 
+	// Socket and buffer configuration values
+	socketMaxBuffer          atomic.Int32
+	socketMinBuffer          atomic.Int32
+	inputProcessingTimeoutMS atomic.Int32
+	maxRestartAttempts       atomic.Int32
+
 	// Batch processing related values
 	BatchProcessingTimeout       time.Duration
 	BatchProcessorFramesPerBatch int

internal/audio/input.go

@@ -65,6 +65,9 @@ func (aim *AudioInputManager) Stop() {
 
 	aim.logComponentStop(AudioInputManagerComponent)
 
+	// Flush any pending sampled metrics before stopping
+	aim.flushPendingMetrics()
+
 	// Stop the IPC-based audio input
 	aim.ipcManager.Stop()
 

internal/audio/input_ipc.go

@@ -942,9 +942,12 @@ func (ais *AudioInputServer) startReaderGoroutine() {
 
 						// If too many consecutive errors, close connection to force reconnect
 						if consecutiveErrors >= maxConsecutiveErrors {
+							// Only log critical errors to reduce hotpath overhead
+							if logger.GetLevel() <= zerolog.ErrorLevel {
 								logger.Error().
 									Int("consecutive_errors", consecutiveErrors).
 									Msg("Too many consecutive read errors, closing connection")
+							}
 
 							ais.mtx.Lock()
 							if ais.conn != nil {
@@ -961,8 +964,11 @@ func (ais *AudioInputServer) startReaderGoroutine() {
 					// Reset error counter on successful read
 					if consecutiveErrors > 0 {
 						consecutiveErrors = 0
+						// Only log recovery info if debug level enabled to reduce overhead
+						if logger.GetLevel() <= zerolog.InfoLevel {
 							logger.Info().Msg("Input connection recovered")
 						}
+					}
 
 					// Send to message channel with non-blocking write
 					select {
@@ -971,7 +977,11 @@ func (ais *AudioInputServer) startReaderGoroutine() {
 					default:
 						// Channel full, drop message
 						atomic.AddInt64(&ais.droppedFrames, 1)
-						logger.Warn().Msg("Message channel full, dropping frame")
+						// Avoid sampling logic in critical path - only log if warn level enabled
+						if logger.GetLevel() <= zerolog.WarnLevel {
+							droppedCount := atomic.LoadInt64(&ais.droppedFrames)
+							logger.Warn().Int64("total_dropped", droppedCount).Msg("Message channel full, dropping frame")
+						}
 					}
 				} else {
 					// No connection, wait briefly before checking again
@@ -985,7 +995,10 @@ func (ais *AudioInputServer) startReaderGoroutine() {
 	logger := logging.GetDefaultLogger().With().Str("component", AudioInputClientComponent).Logger()
 	if !SubmitAudioReaderTask(readerTask) {
 		// If the pool is full or shutting down, fall back to direct goroutine creation
+		// Only log if warn level enabled - avoid sampling logic in critical path
+		if logger.GetLevel() <= zerolog.WarnLevel {
 			logger.Warn().Msg("Audio reader pool full or shutting down, falling back to direct goroutine creation")
+		}
 
 		go readerTask()
 	}

internal/audio/output_streaming.go

@@ -18,11 +18,17 @@ import (
 
 // AudioOutputStreamer manages high-performance audio output streaming
 type AudioOutputStreamer struct {
-	// Performance metrics (atomic operations for thread safety)
+	// Atomic int64 fields MUST be first for ARM32 alignment (8-byte alignment required)
 	processedFrames int64 // Total processed frames counter (atomic)
 	droppedFrames   int64 // Dropped frames counter (atomic)
 	processingTime  int64 // Average processing time in nanoseconds (atomic)
 	lastStatsTime   int64 // Last statistics update time (atomic)
+	frameCounter    int64 // Local counter for sampling
+	localProcessed  int64 // Local processed frame accumulator
+	localDropped    int64 // Local dropped frame accumulator
+
+	// Other fields after atomic int64 fields
+	sampleRate int32 // Sample every N frames (default: 10)
 
 	client     *AudioOutputClient
 	bufferPool *AudioBufferPool
@@ -70,6 +76,7 @@ func NewAudioOutputStreamer() (*AudioOutputStreamer, error) {
 		processingChan: make(chan []byte, GetConfig().ChannelBufferSize), // Large buffer for smooth processing
 		statsInterval:  GetConfig().StatsUpdateInterval,                  // Statistics interval from config
 		lastStatsTime:  time.Now().UnixNano(),
+		sampleRate:     10, // Update metrics every 10 frames to reduce atomic ops
 	}, nil
 }
 
@@ -108,6 +115,9 @@ func (s *AudioOutputStreamer) Stop() {
 	s.running = false
 	s.cancel()
 
+	// Flush any pending sampled metrics before stopping
+	s.flushPendingMetrics()
+
 	// Close processing channel to signal goroutines (only if not already closed)
 	if !s.chanClosed {
 		close(s.processingChan)
@@ -194,12 +204,18 @@ func (s *AudioOutputStreamer) processingLoop() {
 
 	// Set high priority for audio output processing
 	if err := SetAudioThreadPriority(); err != nil {
+		// Only log priority warnings if warn level enabled to reduce overhead
+		if getOutputStreamingLogger().GetLevel() <= zerolog.WarnLevel {
 			getOutputStreamingLogger().Warn().Err(err).Msg("Failed to set audio output processing priority")
 		}
+	}
 	defer func() {
 		if err := ResetThreadPriority(); err != nil {
+			// Only log priority warnings if warn level enabled to reduce overhead
+			if getOutputStreamingLogger().GetLevel() <= zerolog.WarnLevel {
 				getOutputStreamingLogger().Warn().Err(err).Msg("Failed to reset thread priority")
 			}
+		}
 	}()
 
 	for frameData := range s.processingChan {
@@ -209,16 +225,24 @@ func (s *AudioOutputStreamer) processingLoop() {
 
 			if _, err := s.client.ReceiveFrame(); err != nil {
 				if s.client.IsConnected() {
+					// Sample logging to reduce overhead - log every 50th error
+					if atomic.LoadInt64(&s.droppedFrames)%50 == 0 && getOutputStreamingLogger().GetLevel() <= zerolog.WarnLevel {
 						getOutputStreamingLogger().Warn().Err(err).Msg("Error reading audio frame from output server")
-					atomic.AddInt64(&s.droppedFrames, 1)
+					}
+					s.recordFrameDropped()
 				}
 				// Try to reconnect if disconnected
 				if !s.client.IsConnected() {
 					if err := s.client.Connect(); err != nil {
+						// Only log reconnection failures if warn level enabled
+						if getOutputStreamingLogger().GetLevel() <= zerolog.WarnLevel {
 							getOutputStreamingLogger().Warn().Err(err).Msg("Failed to reconnect")
 						}
 					}
 				}
+			} else {
+				s.recordFrameProcessed()
+			}
 		}()
 	}
 }
@@ -258,8 +282,51 @@ func (s *AudioOutputStreamer) reportStatistics() {
 	}
 }
 
-// GetStats returns streaming statistics
+// recordFrameProcessed records a processed frame with sampling optimization
+func (s *AudioOutputStreamer) recordFrameProcessed() {
+	// Increment local counters
+	frameCount := atomic.AddInt64(&s.frameCounter, 1)
+	atomic.AddInt64(&s.localProcessed, 1)
+
+	// Update metrics only every N frames to reduce atomic operation overhead
+	if frameCount%int64(atomic.LoadInt32(&s.sampleRate)) == 0 {
+		// Batch update atomic metrics
+		localProcessed := atomic.SwapInt64(&s.localProcessed, 0)
+		atomic.AddInt64(&s.processedFrames, localProcessed)
+	}
+}
+
+// recordFrameDropped records a dropped frame with sampling optimization
+func (s *AudioOutputStreamer) recordFrameDropped() {
+	// Increment local counter
+	localDropped := atomic.AddInt64(&s.localDropped, 1)
+
+	// Update atomic metrics every N dropped frames
+	if localDropped%int64(atomic.LoadInt32(&s.sampleRate)) == 0 {
+		atomic.AddInt64(&s.droppedFrames, int64(atomic.LoadInt32(&s.sampleRate)))
+		atomic.StoreInt64(&s.localDropped, 0)
+	}
+}
+
+// flushPendingMetrics flushes any pending sampled metrics to atomic counters
+func (s *AudioOutputStreamer) flushPendingMetrics() {
+	// Flush remaining processed and dropped frames
+	localProcessed := atomic.SwapInt64(&s.localProcessed, 0)
+	localDropped := atomic.SwapInt64(&s.localDropped, 0)
+
+	if localProcessed > 0 {
+		atomic.AddInt64(&s.processedFrames, localProcessed)
+	}
+	if localDropped > 0 {
+		atomic.AddInt64(&s.droppedFrames, localDropped)
+	}
+}
+
+// GetStats returns streaming statistics with pending metrics flushed
 func (s *AudioOutputStreamer) GetStats() (processed, dropped int64, avgProcessingTime time.Duration) {
+	// Flush pending metrics for accurate reading
+	s.flushPendingMetrics()
+
 	processed = atomic.LoadInt64(&s.processedFrames)
 	dropped = atomic.LoadInt64(&s.droppedFrames)
 	processingTimeNs := atomic.LoadInt64(&s.processingTime)
@@ -269,6 +336,9 @@ func (s *AudioOutputStreamer) GetStats() (processed, dropped int64, avgProcessin
 
 // GetDetailedStats returns comprehensive streaming statistics
 func (s *AudioOutputStreamer) GetDetailedStats() map[string]interface{} {
+	// Flush pending metrics for accurate reading
+	s.flushPendingMetrics()
+
 	processed := atomic.LoadInt64(&s.processedFrames)
 	dropped := atomic.LoadInt64(&s.droppedFrames)
 	processingTime := atomic.LoadInt64(&s.processingTime)

internal/audio/supervisor.go

@@ -11,6 +11,8 @@ import (
 	"sync/atomic"
 	"syscall"
 	"time"
+
+	"github.com/rs/zerolog"
 )
 
 // Restart configuration is now retrieved from centralized config
@@ -180,16 +182,25 @@ func (s *AudioOutputSupervisor) supervisionLoop() {
 		default:
 			// Start or restart the process
 			if err := s.startProcess(); err != nil {
+				// Only log start errors if error level enabled to reduce overhead
+				if s.logger.GetLevel() <= zerolog.ErrorLevel {
 					s.logger.Error().Err(err).Msg("failed to start audio server process")
+				}
 
 				// Check if we should attempt restart
 				if !s.shouldRestart() {
+					// Only log critical errors to reduce overhead
+					if s.logger.GetLevel() <= zerolog.ErrorLevel {
 						s.logger.Error().Msg("maximum restart attempts exceeded, stopping supervisor")
+					}
 					return
 				}
 
 				delay := s.calculateRestartDelay()
-				s.logger.Warn().Dur("delay", delay).Msg("retrying process start after delay")
+				// Sample logging to reduce overhead - log every 5th restart attempt
+				if len(s.restartAttempts)%5 == 0 && s.logger.GetLevel() <= zerolog.WarnLevel {
+					s.logger.Warn().Dur("delay", delay).Int("attempt", len(s.restartAttempts)).Msg("retrying process start after delay")
+				}
 
 				if s.onRestart != nil {
 					s.onRestart(len(s.restartAttempts), delay)

internal/audio/validation.go

@@ -41,6 +41,7 @@ func ValidateAudioQuality(quality AudioQuality) error {
 }
 
 // ValidateZeroCopyFrame validates zero-copy audio frame
+// Optimized to use cached max frame size
 func ValidateZeroCopyFrame(frame *ZeroCopyAudioFrame) error {
 	if frame == nil {
 		return ErrInvalidFrameData
@@ -49,8 +50,22 @@ func ValidateZeroCopyFrame(frame *ZeroCopyAudioFrame) error {
 	if len(data) == 0 {
 		return ErrInvalidFrameData
 	}
-	// Use config value
-	maxFrameSize := GetConfig().MaxAudioFrameSize
+
+	// Fast path: use cached max frame size
+	maxFrameSize := cachedMaxFrameSize
+	if maxFrameSize == 0 {
+		// Fallback: get from cache
+		cache := GetCachedConfig()
+		maxFrameSize = int(cache.maxAudioFrameSize.Load())
+		if maxFrameSize == 0 {
+			// Last resort: update cache
+			cache.Update()
+			maxFrameSize = int(cache.maxAudioFrameSize.Load())
+		}
+		// Cache globally for next calls
+		cachedMaxFrameSize = maxFrameSize
+	}
+
 	if len(data) > maxFrameSize {
 		return ErrInvalidFrameSize
 	}
@@ -95,10 +110,31 @@ func ValidateThreadPriority(priority int) error {
 }
 
 // ValidateLatency validates latency duration values with reasonable bounds
+// Optimized to use AudioConfigCache for frequently accessed values
 func ValidateLatency(latency time.Duration) error {
 	if latency < 0 {
 		return fmt.Errorf("%w: latency %v cannot be negative", ErrInvalidLatency, latency)
 	}
+
+	// Fast path: check against cached max latency
+	cache := GetCachedConfig()
+	maxLatency := time.Duration(cache.maxLatency.Load())
+
+	// If we have a valid cached value, use it
+	if maxLatency > 0 {
+		minLatency := time.Millisecond // Minimum reasonable latency
+		if latency > 0 && latency < minLatency {
+			return fmt.Errorf("%w: latency %v below minimum %v",
+				ErrInvalidLatency, latency, minLatency)
+		}
+		if latency > maxLatency {
+			return fmt.Errorf("%w: latency %v exceeds maximum %v",
+				ErrInvalidLatency, latency, maxLatency)
+		}
+		return nil
+	}
+
+	// Slower path: full validation with GetConfig()
 	config := GetConfig()
 	minLatency := time.Millisecond // Minimum reasonable latency
 	if latency > 0 && latency < minLatency {
@@ -113,11 +149,30 @@ func ValidateLatency(latency time.Duration) error {
 }
 
 // ValidateMetricsInterval validates metrics update interval
+// Optimized to use AudioConfigCache for frequently accessed values
 func ValidateMetricsInterval(interval time.Duration) error {
-	// Use config values
+	// Fast path: check against cached values
+	cache := GetCachedConfig()
+	minInterval := time.Duration(cache.minMetricsUpdateInterval.Load())
+	maxInterval := time.Duration(cache.maxMetricsUpdateInterval.Load())
+
+	// If we have valid cached values, use them
+	if minInterval > 0 && maxInterval > 0 {
+		if interval < minInterval {
+			return fmt.Errorf("%w: interval %v below minimum %v",
+				ErrInvalidMetricsInterval, interval, minInterval)
+		}
+		if interval > maxInterval {
+			return fmt.Errorf("%w: interval %v exceeds maximum %v",
+				ErrInvalidMetricsInterval, interval, maxInterval)
+		}
+		return nil
+	}
+
+	// Slower path: full validation with GetConfig()
 	config := GetConfig()
-	minInterval := config.MinMetricsUpdateInterval
-	maxInterval := config.MaxMetricsUpdateInterval
+	minInterval = config.MinMetricsUpdateInterval
+	maxInterval = config.MaxMetricsUpdateInterval
 	if interval < minInterval {
 		return ErrInvalidMetricsInterval
 	}
@@ -254,12 +309,18 @@ func ValidateChannelCount(channels int) error {
 		return nil
 	}
 
-	// Check against max channels - still using cache to avoid GetConfig()
-	// Note: We don't have maxChannels in the cache yet, so we'll use GetConfig() for now
-	config := GetConfig()
-	if channels > config.MaxChannels {
+	// Fast path: Check against cached max channels
+	cachedMaxChannels := int(cache.maxChannels.Load())
+	if cachedMaxChannels > 0 && channels <= cachedMaxChannels {
+		return nil
+	}
+
+	// Slow path: Update cache and validate
+	cache.Update()
+	updatedMaxChannels := int(cache.maxChannels.Load())
+	if channels > updatedMaxChannels {
 		return fmt.Errorf("%w: channel count %d exceeds maximum %d",
-			ErrInvalidChannels, channels, config.MaxChannels)
+			ErrInvalidChannels, channels, updatedMaxChannels)
 	}
 	return nil
 }
@@ -331,15 +392,34 @@ func ValidateFrameDuration(duration time.Duration) error {
 		}
 	}
 
-	// Slower path: full validation against min/max
-	config := GetConfig()
-	if duration < config.MinFrameDuration {
+	// Fast path: Check against cached min/max frame duration
+	cachedMinDuration := time.Duration(cache.minFrameDuration.Load())
+	cachedMaxDuration := time.Duration(cache.maxFrameDuration.Load())
+
+	if cachedMinDuration > 0 && cachedMaxDuration > 0 {
+		if duration < cachedMinDuration {
 			return fmt.Errorf("%w: frame duration %v below minimum %v",
-			ErrInvalidFrameDuration, duration, config.MinFrameDuration)
+				ErrInvalidFrameDuration, duration, cachedMinDuration)
 		}
-	if duration > config.MaxFrameDuration {
+		if duration > cachedMaxDuration {
 			return fmt.Errorf("%w: frame duration %v exceeds maximum %v",
-			ErrInvalidFrameDuration, duration, config.MaxFrameDuration)
+				ErrInvalidFrameDuration, duration, cachedMaxDuration)
+		}
+		return nil
+	}
+
+	// Slow path: Update cache and validate
+	cache.Update()
+	updatedMinDuration := time.Duration(cache.minFrameDuration.Load())
+	updatedMaxDuration := time.Duration(cache.maxFrameDuration.Load())
+
+	if duration < updatedMinDuration {
+		return fmt.Errorf("%w: frame duration %v below minimum %v",
+			ErrInvalidFrameDuration, duration, updatedMinDuration)
+	}
+	if duration > updatedMaxDuration {
+		return fmt.Errorf("%w: frame duration %v exceeds maximum %v",
+			ErrInvalidFrameDuration, duration, updatedMaxDuration)
 	}
 	return nil
 }

internal/audio/zero_copy.go

@@ -142,12 +142,13 @@ func NewZeroCopyFramePool(maxFrameSize int) *ZeroCopyFramePool {
 
 // Get retrieves a zero-copy frame from the pool
 func (p *ZeroCopyFramePool) Get() *ZeroCopyAudioFrame {
-	start := time.Now()
+	// Remove metrics overhead in critical path - use sampling instead
 	var wasHit bool
-	defer func() {
-		latency := time.Since(start)
-		GetGranularMetricsCollector().RecordZeroCopyGet(latency, wasHit)
-	}()
+	var startTime time.Time
+	trackMetrics := atomic.LoadInt64(&p.counter)%100 == 0 // Sample 1% of operations
+	if trackMetrics {
+		startTime = time.Now()
+	}
 
 	// Memory guard: Track allocation count to prevent excessive memory usage
 	allocationCount := atomic.LoadInt64(&p.allocationCount)
@@ -161,6 +162,12 @@ func (p *ZeroCopyFramePool) Get() *ZeroCopyAudioFrame {
 		frame.length = 0
 		frame.data = frame.data[:0]
 		frame.mutex.Unlock()
+
+		// Record metrics only for sampled operations
+		if trackMetrics {
+			latency := time.Since(startTime)
+			GetGranularMetricsCollector().RecordZeroCopyGet(latency, wasHit)
+		}
 		return frame
 	}
 
@@ -179,6 +186,12 @@ func (p *ZeroCopyFramePool) Get() *ZeroCopyAudioFrame {
 		frame.mutex.Unlock()
 
 		atomic.AddInt64(&p.hitCount, 1)
+
+		// Record metrics only for sampled operations
+		if trackMetrics {
+			latency := time.Since(startTime)
+			GetGranularMetricsCollector().RecordZeroCopyGet(latency, wasHit)
+		}
 		return frame
 	}
 	p.mutex.Unlock()
@@ -194,16 +207,24 @@ func (p *ZeroCopyFramePool) Get() *ZeroCopyAudioFrame {
 
 	wasHit = true // Pool hit
 	atomic.AddInt64(&p.hitCount, 1)
+
+	// Record metrics only for sampled operations
+	if trackMetrics {
+		latency := time.Since(startTime)
+		GetGranularMetricsCollector().RecordZeroCopyGet(latency, wasHit)
+	}
 	return frame
 }
 
 // Put returns a zero-copy frame to the pool
 func (p *ZeroCopyFramePool) Put(frame *ZeroCopyAudioFrame) {
-	start := time.Now()
-	defer func() {
-		latency := time.Since(start)
-		GetGranularMetricsCollector().RecordZeroCopyPut(latency, frame.capacity)
-	}()
+	// Remove metrics overhead in critical path - use sampling instead
+	var startTime time.Time
+	trackMetrics := atomic.LoadInt64(&p.counter)%100 == 0 // Sample 1% of operations
+	if trackMetrics {
+		startTime = time.Now()
+	}
+
 	if frame == nil || !frame.pooled {
 		return
 	}
@@ -240,6 +261,12 @@ func (p *ZeroCopyFramePool) Put(frame *ZeroCopyAudioFrame) {
 	} else {
 		frame.mutex.Unlock()
 	}
+
+	// Record metrics only for sampled operations
+	if trackMetrics {
+		latency := time.Since(startTime)
+		GetGranularMetricsCollector().RecordZeroCopyPut(latency, frame.capacity)
+	}
 }
 
 // Data returns the frame data as a slice (zero-copy view)