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by revelation 3170 days ago
I've gotten a FTDI down to 2 ms RTT, so if done right (using isochronous transfer) you can get USB down to 1 or max 2 ms. Looking at the latencies quoted here and in the article it's certainly not the problem.

Notice that just getting a thread scheduled every 2 ms is already impossible for Windows, certainly one running a game. You'll get a bunch of outliers within the second. So even if you got your keyboard down to 5 ms, great, but you are not running an operating system that can reliably do something within that timespan!
1 comments
eertami 3170 days ago
>So even if you got your keyboard down to 5 ms, great, but you are not running an operating system that can reliably do something within that timespan!

Maybe I'm not understanding, but that doesn't seem correct.

Most people (gamers) are running mice at 500/1000Hz polling rates and you can easily verify the movement made in each 1-2ms update. (And it is most definitely a noticeable difference going from a standard 125Hz rate to even 500Hz.)

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ssfrr 3170 days ago
Don't confuse throughout and latency. The mouse may be measuring and sending data every 1-2ms, but that doesn't say anything about the latency before the data is handled.
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munchbunny 3170 days ago
This is also a pretty important point: most monitors refresh at 60hz anyway even if your game seems to be measuring much higher framerates, so there's a worst case floor of ~17s on just visuals lagging behind input because you're waiting for the next screen refresh anyway.

The mouse measuring data every 1-2ms will increase the quality of the motion tracking, but it won't necessarily help you with latency unless the data gets to the game fast and the game handles the data quickly.

This explanation by John Carmack comes to mind... it's a good reminder against a lot of the hardware fetishism that is mixed into otherwise good advice about gaming setups. https://superuser.com/questions/419070/transatlantic-ping-fa...

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eertami 3170 days ago
True, though these days 144Hz monitors are everywhere (Personally I used a CRT until LCDs were capable of 120Hz, not sure I could ever go back to 60), makes a big difference I think when down to a 7ms window. Using a mouse at 125 on a modern screen feels really janky.
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