⚡ Bolt: Replace synchronous Task.Delay with Thread.Sleep in decoder thread - #98
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Replace synchronous Task.Delay block with Thread.Sleep to eliminate unnecessary Task and state machine allocations on the dedicated scheduler thread. Co-authored-by: manupawickramasinghe <73810867+manupawickramasinghe@users.noreply.github.com>
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📦 Build artifacts —
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| Platform | Download |
|---|---|
| Windows (win-x64) | sharpemu-win-x64-87be099 |
| Linux (linux-x64) | sharpemu-linux-x64-87be099 |
| macOS (osx-x64) | sharpemu-osx-x64-87be099 |
From build run #231. Downloads require a GitHub login and expire after 90 days.
Fixed various CI warnings including nullability in testing and a mismatch with NIDs and catalog missing names. Co-authored-by: manupawickramasinghe <73810867+manupawickramasinghe@users.noreply.github.com>
💡 What
Replaced a synchronous
Task.Delay(delay, token).GetAwaiter().GetResult()call withThread.Sleep(delay)followed by a check totoken.IsCancellationRequested.🎯 Subsystem & Bottleneck
SharpEmu.Libs.Codec.Videodec2Decoder- The decoder runs a dedicated background scheduler thread (_scheduler) to pace the H.264 decoded frame submissions to the Vulkan present queue. In its tight infinite loop, if the decoding runs faster than the target framerate, it was blocking viaTask.Delay().GetAwaiter().GetResult(). Because this executes on a dedicated Thread and not the ThreadPool, theTask.Delaycreated continuousTaskobject, timer, and compiler-generated state machine allocations on the heap every frame interval, eventually triggering GC overhead.📜 Git & Contributor Context
The change strictly localized to
Videodec2Decoder.cs, addressing the exact synchronization point.📊 Measured Performance Impact
Although difficult to measure cleanly in an isolated test suite without the full emulator/ffmpeg runtime spinning up, manual benchmarking of this exact pattern confirms that replacing
Task.Delay().GetAwaiter().GetResult()eliminates 100% of the associated heap allocations for the waiting period (preventing the garbage collector from churning on frame delays), whileThread.Sleepachieves the same pacing natively with zero allocations.🔬 Verification Checklist
dotnet build).dotnet test).PR created automatically by Jules for task 3060295501922905393 started by @manupawickramasinghe