fix subsequent hls session work ahead (#1419)

CHANGELOG.md

@@ -28,7 +28,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Fix adding alternate schedule
 
 ### Changed
-- Optimize transcoding session to only work ahead (at max speed) for 2 minutes before throttling to realtime
+- Optimize transcoding session to only work ahead (at max speed) for 3 minutes before throttling to realtime
   - This should *greatly* reduce cpu/gpu use when joining a channel, particularly with long content
 - Allow manually editing (typing) schedule item fixed start time
 - Use different control for editing schedule item duration, and allow 24-hour duration

ErsatzTV.Application/Streaming/HlsSessionWorker.cs

@@ -19,6 +19,8 @@ namespace ErsatzTV.Application.Streaming;
 
 public class HlsSessionWorker : IHlsSessionWorker
 {
+    public static readonly TimeSpan WorkAheadDuration = TimeSpan.FromMinutes(3);
+    
     private static readonly SemaphoreSlim Slim = new(1, 1);
     private static int _workAheadCount;
     private readonly IMediator _mediator;
@@ -269,17 +271,27 @@ public class HlsSessionWorker : IHlsSessionWorker
             {
                 Interlocked.Increment(ref _workAheadCount);
                 _logger.LogInformation("HLS segmenter will work ahead for channel {Channel}", _channelNumber);
+                
+                HlsSessionState nextState = _state switch
+                {
+                    HlsSessionState.SeekAndRealtime => HlsSessionState.SeekAndWorkAhead,
+                    HlsSessionState.ZeroAndRealtime => HlsSessionState.ZeroAndWorkAhead,
+                    _ => _state
+                };
+                
+                if (nextState != _state)
+                {
+                    _logger.LogDebug("HLS session state accelerating {Last} => {Next}", _state, nextState);
+                    _state = nextState;
+                }
             }
             else
             {
                 _logger.LogInformation(
                     "HLS segmenter will NOT work ahead for channel {Channel}",
                     _channelNumber);
-            }
 
-            // throttle to realtime if needed
+                // throttle to realtime if needed
-            if (realtime)
-            {
                 HlsSessionState nextState = _state switch
                 {
                     HlsSessionState.SeekAndWorkAhead => HlsSessionState.SeekAndRealtime,

ErsatzTV.Application/Streaming/Queries/GetPlayoutItemProcessByChannelNumberHandler.cs

@@ -182,9 +182,9 @@ public class GetPlayoutItemProcessByChannelNumberHandler : FFmpegProcessHandler<
 
             // _logger.LogDebug("PRE Start: {Start}, Finish {Finish}", start, finish);
             // _logger.LogDebug("PRE in: {In}, out: {Out}", inPoint, outPoint);
-            if (!request.HlsRealtime && duration > TimeSpan.FromMinutes(2))
+            if (!request.HlsRealtime && duration > HlsSessionWorker.WorkAheadDuration)
             {
-                finish = effectiveNow + TimeSpan.FromMinutes(2);
+                finish = effectiveNow + HlsSessionWorker.WorkAheadDuration;
                 outPoint = finish - start + inPoint;
                 isComplete = false;
 

ErsatzTV/Controllers/ArtworkController.cs

@@ -138,9 +138,9 @@ public class ArtworkController : ControllerBase
         CancellationToken cancellationToken)
     {
 #if DEBUG_NO_SYNC
+        await Task.CompletedTask;
         return NotFound();
-#endif
+#else
-
         Either<BaseError, PlexConnectionParametersViewModel> connectionParameters =
             await _mediator.Send(new GetPlexConnectionParameters(plexMediaSourceId), cancellationToken);
 
@@ -165,14 +165,15 @@ public class ArtworkController : ControllerBase
                     stream,
                     response.Content.Headers.ContentType?.MediaType ?? "image/jpeg");
             });
+#endif
     }
 
     private async Task<IActionResult> GetJellyfinArtwork(string path, CancellationToken cancellationToken)
     {
 #if DEBUG_NO_SYNC
+        await Task.CompletedTask;
         return NotFound();
-#endif
+#else
-
         Either<BaseError, JellyfinConnectionParametersViewModel> connectionParameters =
             await _mediator.Send(new GetJellyfinConnectionParameters(), cancellationToken);
 
@@ -196,14 +197,15 @@ public class ArtworkController : ControllerBase
                     stream,
                     response.Content.Headers.ContentType?.MediaType ?? "image/jpeg");
             });
+#endif
     }
 
     private async Task<IActionResult> GetEmbyArtwork(string path, CancellationToken cancellationToken)
     {
 #if DEBUG_NO_SYNC
+        await Task.CompletedTask;
         return NotFound();
-#endif
+#else
-
         Either<BaseError, EmbyConnectionParametersViewModel> connectionParameters =
             await _mediator.Send(new GetEmbyConnectionParameters(), cancellationToken);
 
@@ -227,5 +229,6 @@ public class ArtworkController : ControllerBase
                     stream,
                     response.Content.Headers.ContentType?.MediaType ?? "image/jpeg");
             });
+#endif
     }
 }