Function getZstdEncoderChannel

zstd.go:33–48

getZstdEncoderChannel returns the buffered channel that retains idle zstd encoders for the given params. The slow path holds a single global mutex and re-checks the sync.Map under the lock so that a stampede of goroutines arriving for the same not-yet-seen ZstdEncoderParams cannot create multiple co

(params ZstdEncoderParams)

// the previous size-1 cap can no longer force concurrent callers to
// allocate a fresh encoder per batch.
func getZstdEncoderChannel(params ZstdEncoderParams) chan *zstd.Encoder {
	if c, ok := zstdAvailableEncoders.Load(params); ok {
		return c.(chan *zstd.Encoder)
	}

	zstdEncoderInitMu.Lock()
	defer zstdEncoderInitMu.Unlock()

	if c, ok := zstdAvailableEncoders.Load(params); ok {
		return c.(chan *zstd.Encoder)
	}

	ch := make(chan *zstd.Encoder, max(runtime.GOMAXPROCS(0), 1))
	zstdAvailableEncoders.Store(params, ch)
	return ch
}

func newZstdEncoder(params ZstdEncoderParams) (*zstd.Encoder, error) {
	encoderLevel := zstd.SpeedDefault