Files
jellyfin-ha-src/tests/Jellyfin.Api.Tests/Controllers/DynamicHlsControllerTests.cs
gnattu e2586eed9b Fix concurrent ffmpeg segment racing
This is a nasty one. The failure mode is:

1. Request A started FFmpeg and waited for a segment.
2. Request B requested an earlier or far away segment.
3. Jellyfin thought FFmpeg should to restart at a different position.
4. Request B killed the existing transcoding job.
5. Killing that job cancelled the same token request A was using.
6. The cancellation produced http 500 to request A.

To fix this:

we lock transcoding job state changes and segment handling per playlist, and use a thread safe counter to track how many http responses are still using each job’s segments. A job is only stopped or replaced once that counter reaches zero.
2026-08-05 00:33:42 +08:00

122 lines
4.2 KiB
C#

using System;
using System.Threading;
using System.Threading.Tasks;
using Jellyfin.Api.Controllers;
using MediaBrowser.Controller.MediaEncoding;
using Microsoft.Extensions.Logging.Abstractions;
using Xunit;
namespace Jellyfin.Api.Tests.Controllers
{
public class DynamicHlsControllerTests
{
[Theory]
[MemberData(nameof(GetSegmentLengths_Success_TestData))]
public void GetSegmentLengths_Success(long runtimeTicks, int segmentlength, double[] expected)
{
var res = DynamicHlsController.GetSegmentLengthsInternal(runtimeTicks, segmentlength);
Assert.Equal(expected.Length, res.Length);
for (int i = 0; i < expected.Length; i++)
{
Assert.Equal(expected[i], res[i]);
}
}
public static TheoryData<long, int, double[]> GetSegmentLengths_Success_TestData()
{
var data = new TheoryData<long, int, double[]>();
data.Add(0, 6, Array.Empty<double>());
data.Add(
TimeSpan.FromSeconds(3).Ticks,
6,
new double[] { 3 });
data.Add(
TimeSpan.FromSeconds(6).Ticks,
6,
new double[] { 6 });
data.Add(
TimeSpan.FromSeconds(3.3333333).Ticks,
6,
new double[] { 3.3333333 });
data.Add(
TimeSpan.FromSeconds(9.3333333).Ticks,
6,
new double[] { 6, 3.3333333 });
return data;
}
[Fact]
public async Task WaitForActiveTranscodingRequests_WaitsUntilRequestCompletes()
{
var job = new TranscodingJob(NullLogger<TranscodingJob>.Instance)
{
ActiveRequestCount = 1
};
var waitTask = DynamicHlsController.WaitForActiveTranscodingRequests(job, CancellationToken.None);
Assert.False(waitTask.IsCompleted);
job.DecrementActiveRequestCount();
await waitTask;
}
[Fact]
public async Task WaitForActiveTranscodingRequests_WaitsForEveryRequest()
{
var job = new TranscodingJob(NullLogger<TranscodingJob>.Instance)
{
ActiveRequestCount = 2
};
var waitTask = DynamicHlsController.WaitForActiveTranscodingRequests(job, CancellationToken.None);
job.DecrementActiveRequestCount();
await Task.Delay(150, TestContext.Current.CancellationToken);
Assert.False(waitTask.IsCompleted);
job.DecrementActiveRequestCount();
await waitTask;
}
[Fact]
public async Task WaitForActiveTranscodingRequests_ReturnsWithoutAnActiveRequest()
{
var job = new TranscodingJob(NullLogger<TranscodingJob>.Instance);
await DynamicHlsController.WaitForActiveTranscodingRequests(job, CancellationToken.None);
await DynamicHlsController.WaitForActiveTranscodingRequests(null, CancellationToken.None);
}
[Fact]
public async Task WaitForActiveTranscodingRequests_ObservesCancellation()
{
var job = new TranscodingJob(NullLogger<TranscodingJob>.Instance)
{
ActiveRequestCount = 1
};
using var cancellationTokenSource = new CancellationTokenSource();
var waitTask = DynamicHlsController.WaitForActiveTranscodingRequests(job, cancellationTokenSource.Token);
await cancellationTokenSource.CancelAsync();
await Assert.ThrowsAnyAsync<OperationCanceledException>(() => waitTask);
}
[Fact]
public async Task ActiveRequestCount_UpdatesAtomically()
{
const int RequestCount = 1000;
var job = new TranscodingJob(NullLogger<TranscodingJob>.Instance);
await Task.WhenAll(
Task.Run(() => Parallel.For(0, RequestCount, _ => job.IncrementActiveRequestCount())),
Task.Run(() => Parallel.For(0, RequestCount, _ => job.DecrementActiveRequestCount())));
Assert.Equal(0, job.ActiveRequestCount);
}
}
}