Yup. That niche would be gaming, especially ones that can't use more than 8 threads so the CPUs having more than that many threads will have something extra to do rather than have some threads twiddling their thumbs.
Win2012R2
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Not if it gets CS2 FPS up from 600 to 800.
One would think that computer enthusiast after spectre would understand branch prediction has side effects.
Leaving security aside processing two paths of the branch is a perfect way to trash caches, including TLB.
Now when it comes to pure math reason why it does not make sense branch prediction accuracy is usually >90%. So 10% work is wasted. Scheme when you process 2 sides of the branch gives you exactly 50% waste.
Leaving security aside processing two paths of the branch is a perfect way to trash caches, including TLB.
Now when it comes to pure math reason why it does not make sense branch prediction accuracy is usually >90%. So 10% work is wasted. Scheme when you process 2 sides of the branch gives you exactly 50% waste.
From Agner Fog:
Assuming that a context switch happens in less than 10 clock cycles, that could allow 50% smoother gaming performance on average.
Assuming that a context switch happens in less than 10 clock cycles, that could allow 50% smoother gaming performance on average.
Darkmont
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LPCAMM2 is a ratified JEDEC standard. It’s in the Lenovo ThinkPad P1 Gen 7
Not really. We had the first 5 GHz CPU about 17 years ago. It isn't that long ago we saw the first 6 GHz. I feel pretty confident in this, but feel free to bookmark it (or better screen capture it if the forum doesn't survive) and make me eat crow if I'm wrong!
fastandfurious6
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Saylick
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Done!(or better screen capture it if the forum doesn't survive) and make me eat crow if I'm wrong!
Where can you be reached?
[wider speculative execution]
Re smooth games:
~20 cycles of an e.g. 4 GHz CPU = 5 ns (nanoseconds)¹
frame-to-frame time at e.g. 120 Hz video frame rate: 8 ms (milliseconds, that's million nanosecods)
Also, IIRC 10 ms (milliseconds) is a ballpark under which audio latency needs to stay before musicians perceive a lag while hearing themselves on headphones (i.e. the whole chain of recording, processing, and playing back of live audio, with all the necessary buffering included). I suppose similar measures need to be taken for game audio.
________
¹) The ~20 cycles of penalty of a branch misprediction of which Agner Fog was writing about require that the stalled pipeline can be refilled with instructions and data which do reside in 1st level cache, AFAIU. However, even a last-level cache miss results in "only" a few hundred cycles of a stall, which still is ~five orders of magnitudes smaller than a video frame time. But it follows that [speculative] prefetching of instructions and data is much, much more important for purposes like video game smoothness, compared to speculative execution.
Branching is deciding between two (sometimes more) points in a task to continue at. A context switch is interrupting one task and taking on another.
Re smooth games:
~20 cycles of an e.g. 4 GHz CPU = 5 ns (nanoseconds)¹
frame-to-frame time at e.g. 120 Hz video frame rate: 8 ms (milliseconds, that's million nanosecods)
Also, IIRC 10 ms (milliseconds) is a ballpark under which audio latency needs to stay before musicians perceive a lag while hearing themselves on headphones (i.e. the whole chain of recording, processing, and playing back of live audio, with all the necessary buffering included). I suppose similar measures need to be taken for game audio.
________
¹) The ~20 cycles of penalty of a branch misprediction of which Agner Fog was writing about require that the stalled pipeline can be refilled with instructions and data which do reside in 1st level cache, AFAIU. However, even a last-level cache miss results in "only" a few hundred cycles of a stall, which still is ~five orders of magnitudes smaller than a video frame time. But it follows that [speculative] prefetching of instructions and data is much, much more important for purposes like video game smoothness, compared to speculative execution.
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Win2012R2
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Bad optimisation on the part of game devs and low parallelization of the engine are the causes of that.
Epic can fix the latter, and are in the process of doing so in their UE6 roadmap.
But the former is all on game devs, which have become increasingly lax due to the likes of DLSS/FSR "free lunch" performance increases.
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