feat(audio): add batch write processing and improve thread management

- Add batch write processing functionality to match existing read processing
- Improve thread pinning logic with separate controls for read/write
- Add new batch processing configuration parameters
- Update build tags to exclude arm architecture

internal/audio/audio.go

@@ -1,5 +1,5 @@
-//go:build cgo
-// +build cgo
+//go:build cgo && !arm
+// +build cgo,!arm
 
 // Package audio provides real-time audio processing for JetKVM with low-latency streaming.
 //

internal/audio/batch_audio.go

@@ -1,4 +1,4 @@
-//go:build cgo
+//go:build cgo && !arm
 
 package audio
 
@@ -28,23 +28,31 @@ type BatchAudioProcessor struct {
 
 	// Batch queues and state (atomic for lock-free access)
 	readQueue    chan batchReadRequest
+	writeQueue   chan batchWriteRequest
 	initialized  int32
 	running      int32
 	threadPinned int32
+	writePinned  int32
 
 	// Buffers (pre-allocated to avoid allocation overhead)
-	readBufPool *sync.Pool
+	readBufPool  *sync.Pool
+	writeBufPool *sync.Pool
 }
 
 type BatchAudioStats struct {
 	// int64 fields MUST be first for ARM32 alignment
 	BatchedReads    int64
 	SingleReads     int64
+	BatchedWrites   int64
+	SingleWrites    int64
 	BatchedFrames   int64
 	SingleFrames    int64
+	WriteFrames     int64
 	CGOCallsReduced int64
 	OSThreadPinTime time.Duration // time.Duration is int64 internally
+	WriteThreadTime time.Duration // time.Duration is int64 internally
 	LastBatchTime   time.Time
+	LastWriteTime   time.Time
 }
 
 type batchReadRequest struct {
@@ -58,18 +66,33 @@ type batchReadResult struct {
 	err    error
 }
 
+type batchWriteRequest struct {
+	buffer     []byte
+	resultChan chan batchWriteResult
+	timestamp  time.Time
+}
+
+type batchWriteResult struct {
+	length int
+	err    error
+}
+
 // NewBatchAudioProcessor creates a new batch audio processor
 func NewBatchAudioProcessor(batchSize int, batchDuration time.Duration) *BatchAudioProcessor {
+	// Get cached config to avoid GetConfig() calls
+	cache := GetCachedConfig()
+	cache.Update()
+
 	// Validate input parameters
 	if err := ValidateBufferSize(batchSize); err != nil {
 		logger := logging.GetDefaultLogger().With().Str("component", "batch-audio").Logger()
 		logger.Warn().Err(err).Int("batchSize", batchSize).Msg("invalid batch size, using default")
-		batchSize = GetConfig().BatchProcessorFramesPerBatch
+		batchSize = cache.BatchProcessorFramesPerBatch
 	}
 	if batchDuration <= 0 {
 		logger := logging.GetDefaultLogger().With().Str("component", "batch-audio").Logger()
 		logger.Warn().Dur("batchDuration", batchDuration).Msg("invalid batch duration, using default")
-		batchDuration = GetConfig().BatchProcessingDelay
+		batchDuration = cache.BatchProcessingDelay
 	}
 
 	ctx, cancel := context.WithCancel(context.Background())
@@ -82,11 +105,17 @@ func NewBatchAudioProcessor(batchSize int, batchDuration time.Duration) *BatchAu
 		batchSize:     batchSize,
 		batchDuration: batchDuration,
 		readQueue:     make(chan batchReadRequest, batchSize*2),
+		writeQueue:    make(chan batchWriteRequest, batchSize*2),
 		readBufPool: &sync.Pool{
 			New: func() interface{} {
 				return make([]byte, GetConfig().AudioFramePoolSize) // Max audio frame size
 			},
 		},
+		writeBufPool: &sync.Pool{
+			New: func() interface{} {
+				return make([]byte, GetConfig().AudioFramePoolSize) // Max audio frame size
+			},
+		},
 	}
 
 	return processor
@@ -105,6 +134,7 @@ func (bap *BatchAudioProcessor) Start() error {
 
 	// Start batch processing goroutines
 	go bap.batchReadProcessor()
+	go bap.batchWriteProcessor()
 
 	bap.logger.Info().Int("batch_size", bap.batchSize).
 		Dur("batch_duration", bap.batchDuration).
@@ -129,13 +159,17 @@ func (bap *BatchAudioProcessor) Stop() {
 
 // BatchReadEncode performs batched audio read and encode operations
 func (bap *BatchAudioProcessor) BatchReadEncode(buffer []byte) (int, error) {
+	// Get cached config to avoid GetConfig() calls in hot path
+	cache := GetCachedConfig()
+	cache.Update()
+
 	// Validate buffer before processing
 	if err := ValidateBufferSize(len(buffer)); err != nil {
 		bap.logger.Debug().Err(err).Msg("invalid buffer for batch processing")
 		return 0, err
 	}
 
-	if atomic.LoadInt32(&bap.running) == 0 {
+	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)
@@ -149,21 +183,22 @@ func (bap *BatchAudioProcessor) BatchReadEncode(buffer []byte) (int, error) {
 		timestamp:  time.Now(),
 	}
 
+	// Try to queue the request with non-blocking send
 	select {
 	case bap.readQueue <- request:
 		// Successfully queued
-	case <-time.After(GetConfig().ShortTimeout):
-		// Queue is full or blocked, fallback to single operation
+	default:
+		// Queue is full, fallback to single operation
 		atomic.AddInt64(&bap.stats.SingleReads, 1)
 		atomic.AddInt64(&bap.stats.SingleFrames, 1)
 		return CGOAudioReadEncode(buffer)
 	}
 
-	// Wait for result
+	// Wait for result with timeout
 	select {
 	case result := <-resultChan:
 		return result.length, result.err
-	case <-time.After(GetConfig().MediumTimeout):
+	case <-time.After(cache.BatchProcessingTimeout):
 		// Timeout, fallback to single operation
 		atomic.AddInt64(&bap.stats.SingleReads, 1)
 		atomic.AddInt64(&bap.stats.SingleFrames, 1)
@@ -171,6 +206,54 @@ func (bap *BatchAudioProcessor) BatchReadEncode(buffer []byte) (int, error) {
 	}
 }
 
+// BatchDecodeWrite performs batched audio decode and write operations
+func (bap *BatchAudioProcessor) BatchDecodeWrite(buffer []byte) (int, error) {
+	// Get cached config to avoid GetConfig() calls in hot path
+	cache := GetCachedConfig()
+	cache.Update()
+
+	// Validate buffer before processing
+	if err := ValidateBufferSize(len(buffer)); err != nil {
+		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)
+		return CGOAudioDecodeWrite(buffer)
+	}
+
+	resultChan := make(chan batchWriteResult, 1)
+	request := batchWriteRequest{
+		buffer:     buffer,
+		resultChan: resultChan,
+		timestamp:  time.Now(),
+	}
+
+	// Try to queue the request with non-blocking send
+	select {
+	case bap.writeQueue <- request:
+		// Successfully queued
+	default:
+		// Queue is full, fall back to single operation
+		atomic.AddInt64(&bap.stats.SingleWrites, 1)
+		atomic.AddInt64(&bap.stats.WriteFrames, 1)
+		return CGOAudioDecodeWrite(buffer)
+	}
+
+	// Wait for result with timeout
+	select {
+	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)
+		return CGOAudioDecodeWrite(buffer)
+	}
+}
+
 // batchReadProcessor processes batched read operations
 func (bap *BatchAudioProcessor) batchReadProcessor() {
 	defer bap.logger.Debug().Msg("batch read processor stopped")
@@ -207,15 +290,54 @@ func (bap *BatchAudioProcessor) batchReadProcessor() {
 	}
 }
 
+// batchWriteProcessor processes batched write operations
+func (bap *BatchAudioProcessor) batchWriteProcessor() {
+	defer bap.logger.Debug().Msg("batch write processor stopped")
+
+	ticker := time.NewTicker(bap.batchDuration)
+	defer ticker.Stop()
+
+	var batch []batchWriteRequest
+	batch = make([]batchWriteRequest, 0, bap.batchSize)
+
+	for atomic.LoadInt32(&bap.running) == 1 {
+		select {
+		case <-bap.ctx.Done():
+			return
+
+		case req := <-bap.writeQueue:
+			batch = append(batch, req)
+			if len(batch) >= bap.batchSize {
+				bap.processBatchWrite(batch)
+				batch = batch[:0] // Clear slice but keep capacity
+			}
+
+		case <-ticker.C:
+			if len(batch) > 0 {
+				bap.processBatchWrite(batch)
+				batch = batch[:0] // Clear slice but keep capacity
+			}
+		}
+	}
+
+	// Process any remaining requests
+	if len(batch) > 0 {
+		bap.processBatchWrite(batch)
+	}
+}
+
 // processBatchRead processes a batch of read requests efficiently
 func (bap *BatchAudioProcessor) processBatchRead(batch []batchReadRequest) {
 	if len(batch) == 0 {
 		return
 	}
 
+	// Get cached config to avoid GetConfig() calls in hot path
+	cache := GetCachedConfig()
+
 	// Only pin to OS thread for large batches to reduce thread contention
 	start := time.Now()
-	shouldPinThread := len(batch) >= GetConfig().MinBatchSizeForThreadPinning
+	shouldPinThread := len(batch) >= cache.MinBatchSizeForThreadPinning
 
 	// Track if we pinned the thread in this call
 	threadWasPinned := false
@@ -268,16 +390,85 @@ func (bap *BatchAudioProcessor) processBatchRead(batch []batchReadRequest) {
 	bap.stats.LastBatchTime = time.Now()
 }
 
+// processBatchWrite processes a batch of write requests efficiently
+func (bap *BatchAudioProcessor) processBatchWrite(batch []batchWriteRequest) {
+	if len(batch) == 0 {
+		return
+	}
+
+	// Get cached config to avoid GetConfig() calls in hot path
+	cache := GetCachedConfig()
+
+	// Only pin to OS thread for large batches to reduce thread contention
+	start := time.Now()
+	shouldPinThread := len(batch) >= cache.MinBatchSizeForThreadPinning
+
+	// Track if we pinned the thread in this call
+	threadWasPinned := false
+
+	if shouldPinThread && atomic.CompareAndSwapInt32(&bap.writePinned, 0, 1) {
+		threadWasPinned = true
+		runtime.LockOSThread()
+
+		// Set high priority for batch audio processing
+		if err := SetAudioThreadPriority(); err != nil {
+			bap.logger.Warn().Err(err).Msg("failed to set batch audio processing priority")
+		}
+	}
+
+	batchSize := len(batch)
+	atomic.AddInt64(&bap.stats.BatchedWrites, 1)
+	atomic.AddInt64(&bap.stats.WriteFrames, int64(batchSize))
+	if batchSize > 1 {
+		atomic.AddInt64(&bap.stats.CGOCallsReduced, int64(batchSize-1))
+	}
+
+	// Add deferred function to release thread lock if we pinned it
+	if threadWasPinned {
+		defer func() {
+			if err := ResetThreadPriority(); err != nil {
+				bap.logger.Warn().Err(err).Msg("failed to reset thread priority")
+			}
+			runtime.UnlockOSThread()
+			atomic.StoreInt32(&bap.writePinned, 0)
+			bap.stats.WriteThreadTime += time.Since(start)
+		}()
+	}
+
+	// Process each request in the batch
+	for _, req := range batch {
+		length, err := CGOAudioDecodeWrite(req.buffer)
+		result := batchWriteResult{
+			length: length,
+			err:    err,
+		}
+
+		// Send result back (non-blocking)
+		select {
+		case req.resultChan <- result:
+		default:
+			// Requestor timed out, drop result
+		}
+	}
+
+	bap.stats.LastWriteTime = time.Now()
+}
+
 // GetStats returns current batch processor statistics
 func (bap *BatchAudioProcessor) GetStats() BatchAudioStats {
 	return BatchAudioStats{
 		BatchedReads:    atomic.LoadInt64(&bap.stats.BatchedReads),
 		SingleReads:     atomic.LoadInt64(&bap.stats.SingleReads),
+		BatchedWrites:   atomic.LoadInt64(&bap.stats.BatchedWrites),
+		SingleWrites:    atomic.LoadInt64(&bap.stats.SingleWrites),
 		BatchedFrames:   atomic.LoadInt64(&bap.stats.BatchedFrames),
 		SingleFrames:    atomic.LoadInt64(&bap.stats.SingleFrames),
+		WriteFrames:     atomic.LoadInt64(&bap.stats.WriteFrames),
 		CGOCallsReduced: atomic.LoadInt64(&bap.stats.CGOCallsReduced),
 		OSThreadPinTime: bap.stats.OSThreadPinTime,
+		WriteThreadTime: bap.stats.WriteThreadTime,
 		LastBatchTime:   bap.stats.LastBatchTime,
+		LastWriteTime:   bap.stats.LastWriteTime,
 	}
 }
 
@@ -301,8 +492,11 @@ func GetBatchAudioProcessor() *BatchAudioProcessor {
 
 	// Initialize on first use
 	if atomic.CompareAndSwapInt32(&batchProcessorInitialized, 0, 1) {
-		config := GetConfig()
-		processor := NewBatchAudioProcessor(config.BatchProcessorFramesPerBatch, config.BatchProcessorTimeout)
+		// Get cached config to avoid GetConfig() calls
+		cache := GetCachedConfig()
+		cache.Update()
+
+		processor := NewBatchAudioProcessor(cache.BatchProcessorFramesPerBatch, cache.BatchProcessorTimeout)
 		atomic.StorePointer(&globalBatchProcessor, unsafe.Pointer(processor))
 		return processor
 	}
@@ -336,8 +530,21 @@ func DisableBatchAudioProcessing() {
 // BatchCGOAudioReadEncode is a batched version of CGOAudioReadEncode
 func BatchCGOAudioReadEncode(buffer []byte) (int, error) {
 	processor := GetBatchAudioProcessor()
-	if processor != nil && processor.IsRunning() {
-		return processor.BatchReadEncode(buffer)
+	if processor == nil || !processor.IsRunning() {
+		// Fall back to non-batched version if processor is not running
+		return CGOAudioReadEncode(buffer)
 	}
-	return CGOAudioReadEncode(buffer)
+
+	return processor.BatchReadEncode(buffer)
+}
+
+// BatchCGOAudioDecodeWrite is a batched version of CGOAudioDecodeWrite
+func BatchCGOAudioDecodeWrite(buffer []byte) (int, error) {
+	processor := GetBatchAudioProcessor()
+	if processor == nil || !processor.IsRunning() {
+		// Fall back to non-batched version if processor is not running
+		return CGOAudioDecodeWrite(buffer)
+	}
+
+	return processor.BatchDecodeWrite(buffer)
 }

internal/audio/buffer_pool.go

@@ -1,5 +1,5 @@
-//go:build cgo
-// +build cgo
+//go:build cgo && !arm
+// +build cgo,!arm
 
 package audio
 

internal/audio/cgo_audio.go

@@ -1,4 +1,4 @@
-//go:build cgo
+//go:build cgo && !arm
 
 package audio
 
@@ -735,6 +735,13 @@ type AudioConfigCache struct {
 	minOpusBitrate    atomic.Int32
 	maxOpusBitrate    atomic.Int32
 
+	// Batch processing related values
+	BatchProcessingTimeout       time.Duration
+	BatchProcessorFramesPerBatch int
+	BatchProcessorTimeout        time.Duration
+	BatchProcessingDelay         time.Duration
+	MinBatchSizeForThreadPinning int
+
 	// Mutex for updating the cache
 	mutex       sync.RWMutex
 	lastUpdate  time.Time
@@ -799,6 +806,13 @@ func (c *AudioConfigCache) Update() {
 		c.minOpusBitrate.Store(int32(config.MinOpusBitrate))
 		c.maxOpusBitrate.Store(int32(config.MaxOpusBitrate))
 
+		// Update batch processing related values
+		c.BatchProcessingTimeout = 100 * time.Millisecond // Fixed timeout for batch processing
+		c.BatchProcessorFramesPerBatch = config.BatchProcessorFramesPerBatch
+		c.BatchProcessorTimeout = config.BatchProcessorTimeout
+		c.BatchProcessingDelay = config.BatchProcessingDelay
+		c.MinBatchSizeForThreadPinning = config.MinBatchSizeForThreadPinning
+
 		// Pre-allocate common errors
 		c.bufferTooSmallReadEncode = newBufferTooSmallError(0, config.MinReadEncodeBuffer)
 		c.bufferTooLargeDecodeWrite = newBufferTooLargeError(config.MaxDecodeWriteBuffer+1, config.MaxDecodeWriteBuffer)

internal/audio/output_streaming.go

@@ -1,5 +1,5 @@
-//go:build cgo
-// +build cgo
+//go:build cgo && !arm
+// +build cgo,!arm
 
 package audio
 

internal/audio/supervisor.go

@@ -1,5 +1,5 @@
-//go:build cgo
-// +build cgo
+//go:build cgo && !arm
+// +build cgo,!arm
 
 package audio