diff options
Diffstat (limited to 'MediaBrowser.Controller/MediaEncoding/TranscodingThrottler.cs')
| -rw-r--r-- | MediaBrowser.Controller/MediaEncoding/TranscodingThrottler.cs | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/MediaBrowser.Controller/MediaEncoding/TranscodingThrottler.cs b/MediaBrowser.Controller/MediaEncoding/TranscodingThrottler.cs new file mode 100644 index 000000000..aa08af54f --- /dev/null +++ b/MediaBrowser.Controller/MediaEncoding/TranscodingThrottler.cs @@ -0,0 +1,218 @@ +using System; +using System.Threading; +using System.Threading.Tasks; +using MediaBrowser.Common.Configuration; +using MediaBrowser.Model.Configuration; +using MediaBrowser.Model.IO; +using Microsoft.Extensions.Logging; + +namespace MediaBrowser.Controller.MediaEncoding; + +/// <summary> +/// Transcoding throttler. +/// </summary> +public class TranscodingThrottler : IDisposable +{ + private readonly TranscodingJobDto _job; + private readonly ILogger<TranscodingThrottler> _logger; + private readonly IConfigurationManager _config; + private readonly IFileSystem _fileSystem; + private readonly IMediaEncoder _mediaEncoder; + private Timer? _timer; + private bool _isPaused; + + /// <summary> + /// Initializes a new instance of the <see cref="TranscodingThrottler"/> class. + /// </summary> + /// <param name="job">Transcoding job dto.</param> + /// <param name="logger">Instance of the <see cref="ILogger{TranscodingThrottler}"/> interface.</param> + /// <param name="config">Instance of the <see cref="IConfigurationManager"/> interface.</param> + /// <param name="fileSystem">Instance of the <see cref="IFileSystem"/> interface.</param> + /// <param name="mediaEncoder">Instance of the <see cref="IMediaEncoder"/> interface.</param> + public TranscodingThrottler(TranscodingJobDto job, ILogger<TranscodingThrottler> logger, IConfigurationManager config, IFileSystem fileSystem, IMediaEncoder mediaEncoder) + { + _job = job; + _logger = logger; + _config = config; + _fileSystem = fileSystem; + _mediaEncoder = mediaEncoder; + } + + /// <summary> + /// Start timer. + /// </summary> + public void Start() + { + _timer = new Timer(TimerCallback, null, 5000, 5000); + } + + /// <summary> + /// Unpause transcoding. + /// </summary> + /// <returns>A <see cref="Task"/>.</returns> + public async Task UnpauseTranscoding() + { + if (_isPaused) + { + _logger.LogDebug("Sending resume command to ffmpeg"); + + try + { + var resumeKey = _mediaEncoder.IsPkeyPauseSupported ? "u" : Environment.NewLine; + await _job.Process!.StandardInput.WriteAsync(resumeKey).ConfigureAwait(false); + _isPaused = false; + } + catch (Exception ex) + { + _logger.LogError(ex, "Error resuming transcoding"); + } + } + } + + /// <summary> + /// Stop throttler. + /// </summary> + /// <returns>A <see cref="Task"/>.</returns> + public async Task Stop() + { + DisposeTimer(); + await UnpauseTranscoding().ConfigureAwait(false); + } + + /// <summary> + /// Dispose throttler. + /// </summary> + public void Dispose() + { + Dispose(true); + GC.SuppressFinalize(this); + } + + /// <summary> + /// Dispose throttler. + /// </summary> + /// <param name="disposing">Disposing.</param> + protected virtual void Dispose(bool disposing) + { + if (disposing) + { + DisposeTimer(); + } + } + + private EncodingOptions GetOptions() + { + return _config.GetEncodingOptions(); + } + + private async void TimerCallback(object? state) + { + if (_job.HasExited) + { + DisposeTimer(); + return; + } + + var options = GetOptions(); + + if (options.EnableThrottling && IsThrottleAllowed(_job, options.ThrottleDelaySeconds)) + { + await PauseTranscoding().ConfigureAwait(false); + } + else + { + await UnpauseTranscoding().ConfigureAwait(false); + } + } + + private async Task PauseTranscoding() + { + if (!_isPaused) + { + var pauseKey = _mediaEncoder.IsPkeyPauseSupported ? "p" : "c"; + + _logger.LogDebug("Sending pause command [{Key}] to ffmpeg", pauseKey); + + try + { + await _job.Process!.StandardInput.WriteAsync(pauseKey).ConfigureAwait(false); + _isPaused = true; + } + catch (Exception ex) + { + _logger.LogError(ex, "Error pausing transcoding"); + } + } + } + + private bool IsThrottleAllowed(TranscodingJobDto job, int thresholdSeconds) + { + var bytesDownloaded = job.BytesDownloaded; + var transcodingPositionTicks = job.TranscodingPositionTicks ?? 0; + var downloadPositionTicks = job.DownloadPositionTicks ?? 0; + + var path = job.Path ?? throw new ArgumentException("Path can't be null."); + + var gapLengthInTicks = TimeSpan.FromSeconds(thresholdSeconds).Ticks; + + if (downloadPositionTicks > 0 && transcodingPositionTicks > 0) + { + // HLS - time-based consideration + + var targetGap = gapLengthInTicks; + var gap = transcodingPositionTicks - downloadPositionTicks; + + if (gap < targetGap) + { + _logger.LogDebug("Not throttling transcoder gap {0} target gap {1}", gap, targetGap); + return false; + } + + _logger.LogDebug("Throttling transcoder gap {0} target gap {1}", gap, targetGap); + return true; + } + + if (bytesDownloaded > 0 && transcodingPositionTicks > 0) + { + // Progressive Streaming - byte-based consideration + + try + { + var bytesTranscoded = job.BytesTranscoded ?? _fileSystem.GetFileInfo(path).Length; + + // Estimate the bytes the transcoder should be ahead + double gapFactor = gapLengthInTicks; + gapFactor /= transcodingPositionTicks; + var targetGap = bytesTranscoded * gapFactor; + + var gap = bytesTranscoded - bytesDownloaded; + + if (gap < targetGap) + { + _logger.LogDebug("Not throttling transcoder gap {0} target gap {1} bytes downloaded {2}", gap, targetGap, bytesDownloaded); + return false; + } + + _logger.LogDebug("Throttling transcoder gap {0} target gap {1} bytes downloaded {2}", gap, targetGap, bytesDownloaded); + return true; + } + catch (Exception ex) + { + _logger.LogError(ex, "Error getting output size"); + return false; + } + } + + _logger.LogDebug("No throttle data for {Path}", path); + return false; + } + + private void DisposeTimer() + { + if (_timer is not null) + { + _timer.Dispose(); + _timer = null; + } + } +} |