6 ms·

Toys/Lag: Jerk Monitor

54 points by ptramo 1y ago

ptramo 1y ago
With 240 Hz displays you probably want your mouse polling setting at 4000 or better 8000 Hz. This tool lets anyone confirm that on their hardware.
- BearOso 1y ago
  That's a recent invention. Only the latest gaming mice can poll at that rate, and not particularly well on USB2. They're usually limited to 1000. Neat tool, though. I'm also very sensitive towards latency.
  - mrheosuper 1y ago
    most of 8k dongle is usb 2
    - BearOso 1y ago
      Of course, that's necessary. Many USB ports "designated" for keyboard and mice are still only USB 1.1, and my post should have said unless on USB 2. You need USB 2 in both the mouse/adaptor and port to get full performance.
naoru 1y ago
Seems like it doesn't properly handle mouse events on Safari in macOS and only shows "frames with no pointer events". I assume it's because "pointerrawupdate" event is not supported there. Also it's interesting that with ProMotion enabled it reports 16.67ms per frame (indicating 60Hz redraw rate) in Safari, but in Chrome it's 8.33.
- ptramo 1y ago
  Yes, I rely on pointerrawupdate. Thanks for letting me know! Unfortunately pointermove is typically synced with graphics in my limited experience, and I think I'd rather not show anything than provide wildly inaccurate numbers.
  - naoru 1y ago
    Oh and you also might be interested in this one too: https://github.com/cakama3a/Polling https://github.com/cakama3a/Polling Although it's for gamepads, it's pretty much indispensable in debugging gamepad-related latency issues. For example, I found that my presumably 1000Hz controller can do only 500Hz in ideal conditions and it starts to drop at a much lower distance from the computer than advertised. Neat stuff.
wkat4242 1y ago
[flagged]
- notfed 1y ago
  [flagged]
- deleted 1y ago
  [deleted]
daft_pink 1y ago
I found that plugging my keyboards directly into my Mac’s limited USB ports is noticably faster. I’m curious if there is a USB hub that I could buy of higher quality as my mac doesn’t have too much i/o
- lostlogin 1y ago
  ‘USB hub’ and ‘quality’ never go together. I’d love to be wrong on this but haven’t been so far.
  - daft_pink 1y ago
    Buying a $160 thunderbolt 5 hub for my keyboard? Lol
sillysaurusx 1y ago
I can buy that humans can see at least 120hz at a minimum. 60Hz is the generally accepted threshold, but I’ve long suspected that 120Hz has mostly imperceptible effects that are still noticeable, if rarely. I can’t buy this: > I've also learnt I do benefit from the 8 kHz setting of my mouse, as even at 3200 DPI with fast & smooth motion, some frames still miss a pointer update It may be true that pointer updates were being missed. But does that really affect anything? It turns out that there’s a way to test this experimentally. Do a double blind experiment, just like in science. If you can tell which monitor is 240hz more than randomly, then it matters. Ditto for the pointer updates. The corollary is that if you can’t tell with better than random chance, then none of this matters, no matter how much you think it does. Experiments like this have decisively settled the “Does higher sampling rate matter when listening to music?” debate, among other questions. People still swear that they can tell that there’s a difference, but it’s expectation bias. They’re mistaken. (10ms drops every few seconds would definitely be noticeable though; that wasn’t the point.)
- ptramo 1y ago
  As per the post, I wrote this tool to confirm I was getting jerks of ~10ms every few seconds on one USB port and not the other. This would _suggest_ I can catch differences around the ballpark of 100 Hz. I'm game for a randomized blinded test on 120 Hz refresh rate vs 240 Hz refresh rate. I would indeed be very curious to confirm I can tell the difference with a proper protocol. Many years back (we were on CRTs), I was in similar shoes, convinced my friend couldn't tell the difference between 60 Hz and 90 Hz when playing video games. Turns out he only needed to look at the pointer through one push of the mouse to tell right away, successful 100% of the time in a blinded experiment.
  - ptramo 1y ago
    As to how you can perceive the difference between 120 events per second and 240, I have what I hope is a fairly simple explanation. It's like lightning strokes of tens of microseconds making a lasting impression on your perception of the scene. You don't "count" strokes over time, but in space. When you make circles fast and large enough on screen, you can evaluate the number of cursors that appear before your eyes. At 4 circles per second, is each circle made of ~60 pointers or ~30? Belief not fact: it's not hard to guess.
xnx 1y ago
Does this tool measure something different than? https://joltfly.com/mouse-latency-test/ https://joltfly.com/mouse-latency-test/
- ptramo 1y ago
  Yes, pointerrawupdate events for this one, mousemove for the one you linked. The latter tends to sync to the display in my very limited experience. There are other differences in the tools, mine was designed for what I wanted to understand so I'm biased toward it.
jerlam 1y ago
I bought a Logitech wireless mouse called the Marathon which boasted an amazing three-year battery life on two AAs. I initially thought it was broken; it had a maddening delay where the sensors turned off after a short idle time, so when I wanted to use the mouse, it didn't register the first movements since it had to "wake up". This delay wasn't present on the Logitech gaming mouse I previously used, probably a combination of a high polling rate (500Hz) and a much longer idle delay. The battery life was also much shorter, only 250 hours on high-performance mode, but I just recharged a set of AA batteries every week so it was never an issue. I ended up returning the Marathon mouse.
- jonathanlydall 1y ago
  I’m happy with my $5 wired Logitech mouse as it’s got essentially zero lag, never runs out of batteries and unlike the high end Logitech mice has no “rubber” which tends to invariably go icky over time. At one point I had a Razer wireless mouse (Mamba I think?) which had no discernible latency and a nice dock for recharging the mouse, I was very happy with it until one evening it just stopped working. While alone in my flat, I stepped away from using my computer for about an hour, didn’t even put it to sleep, came back, and it would no longer move but would still register mouse clicks. I tried contacting customer support asking if there was a way to reset it or reflash the firmware or something and they’re just like “nope”. Last piece of Razer hardware I ever bought.
rufus_foreman 1y ago
Sometimes I think "Uncontrollable Urge" is the greatest Devo song ever. Other times, I think maybe "Jerk Monitor".
TheTon 1y ago
Several years ago, a coworker made an Arduino "mouse" that traced a square with a 1KHz report rate. Multiple systems running Windows 10 and reading mouse updates via either regular window events or the Win32 raw mouse API would occasionally lose events, meaning the square would drift over time. We tried both with a custom app and with drawing programs like Paint. We could not reproduce the issue on systems running macOS or Linux, and we chalked it up to a bug in Windows. It was hard to know if it affected real mice but I expect it did. I haven’t tried retesting with more recent versions of Windows to see if it is fixed, maybe it has been. Anyway, I’m not disputing OPs claim, I can totally believe it, but I always thought it was funny that pro gamers on Windows with high end mice could be losing the occasional movement and apparently nobody noticed that.

54 points by ptramo 1y ago

With 240 Hz displays you probably want your mouse polling setting at 4000 or better 8000 Hz. This tool lets anyone confirm that on their hardware.

BearOso 1y ago
That's a recent invention. Only the latest gaming mice can poll at that rate, and not particularly well on USB2. They're usually limited to 1000. Neat tool, though. I'm also very sensitive towards latency.
- mrheosuper 1y ago
  most of 8k dongle is usb 2
  - BearOso 1y ago
    Of course, that's necessary. Many USB ports "designated" for keyboard and mice are still only USB 1.1, and my post should have said unless on USB 2. You need USB 2 in both the mouse/adaptor and port to get full performance.

naoru 1y ago

Seems like it doesn't properly handle mouse events on Safari in macOS and only shows "frames with no pointer events". I assume it's because "pointerrawupdate" event is not supported there. Also it's interesting that with ProMotion enabled it reports 16.67ms per frame (indicating 60Hz redraw rate) in Safari, but in Chrome it's 8.33.

ptramo 1y ago
Yes, I rely on pointerrawupdate. Thanks for letting me know! Unfortunately pointermove is typically synced with graphics in my limited experience, and I think I'd rather not show anything than provide wildly inaccurate numbers.
- naoru 1y ago
  Oh and you also might be interested in this one too: https://github.com/cakama3a/Polling https://github.com/cakama3a/Polling Although it's for gamepads, it's pretty much indispensable in debugging gamepad-related latency issues. For example, I found that my presumably 1000Hz controller can do only 500Hz in ideal conditions and it starts to drop at a much lower distance from the computer than advertised. Neat stuff.

wkat4242 1y ago

[flagged]

notfed 1y ago
[flagged]
deleted 1y ago
[deleted]

daft_pink 1y ago

I found that plugging my keyboards directly into my Mac’s limited USB ports is noticably faster. I’m curious if there is a USB hub that I could buy of higher quality as my mac doesn’t have too much i/o

lostlogin 1y ago
‘USB hub’ and ‘quality’ never go together. I’d love to be wrong on this but haven’t been so far.
- daft_pink 1y ago
  Buying a $160 thunderbolt 5 hub for my keyboard? Lol

sillysaurusx 1y ago

I can buy that humans can see at least 120hz at a minimum. 60Hz is the generally accepted threshold, but I’ve long suspected that 120Hz has mostly imperceptible effects that are still noticeable, if rarely. I can’t buy this: > I've also learnt I do benefit from the 8 kHz setting of my mouse, as even at 3200 DPI with fast & smooth motion, some frames still miss a pointer update It may be true that pointer updates were being missed. But does that really affect anything? It turns out that there’s a way to test this experimentally. Do a double blind experiment, just like in science. If you can tell which monitor is 240hz more than randomly, then it matters. Ditto for the pointer updates. The corollary is that if you can’t tell with better than random chance, then none of this matters, no matter how much you think it does. Experiments like this have decisively settled the “Does higher sampling rate matter when listening to music?” debate, among other questions. People still swear that they can tell that there’s a difference, but it’s expectation bias. They’re mistaken. (10ms drops every few seconds would definitely be noticeable though; that wasn’t the point.)

ptramo 1y ago
As per the post, I wrote this tool to confirm I was getting jerks of ~10ms every few seconds on one USB port and not the other. This would _suggest_ I can catch differences around the ballpark of 100 Hz. I'm game for a randomized blinded test on 120 Hz refresh rate vs 240 Hz refresh rate. I would indeed be very curious to confirm I can tell the difference with a proper protocol. Many years back (we were on CRTs), I was in similar shoes, convinced my friend couldn't tell the difference between 60 Hz and 90 Hz when playing video games. Turns out he only needed to look at the pointer through one push of the mouse to tell right away, successful 100% of the time in a blinded experiment.
- ptramo 1y ago
  As to how you can perceive the difference between 120 events per second and 240, I have what I hope is a fairly simple explanation. It's like lightning strokes of tens of microseconds making a lasting impression on your perception of the scene. You don't "count" strokes over time, but in space. When you make circles fast and large enough on screen, you can evaluate the number of cursors that appear before your eyes. At 4 circles per second, is each circle made of ~60 pointers or ~30? Belief not fact: it's not hard to guess.

xnx 1y ago

Does this tool measure something different than? https://joltfly.com/mouse-latency-test/ https://joltfly.com/mouse-latency-test/

ptramo 1y ago
Yes, pointerrawupdate events for this one, mousemove for the one you linked. The latter tends to sync to the display in my very limited experience. There are other differences in the tools, mine was designed for what I wanted to understand so I'm biased toward it.

jerlam 1y ago

I bought a Logitech wireless mouse called the Marathon which boasted an amazing three-year battery life on two AAs. I initially thought it was broken; it had a maddening delay where the sensors turned off after a short idle time, so when I wanted to use the mouse, it didn't register the first movements since it had to "wake up". This delay wasn't present on the Logitech gaming mouse I previously used, probably a combination of a high polling rate (500Hz) and a much longer idle delay. The battery life was also much shorter, only 250 hours on high-performance mode, but I just recharged a set of AA batteries every week so it was never an issue. I ended up returning the Marathon mouse.

jonathanlydall 1y ago
I’m happy with my $5 wired Logitech mouse as it’s got essentially zero lag, never runs out of batteries and unlike the high end Logitech mice has no “rubber” which tends to invariably go icky over time. At one point I had a Razer wireless mouse (Mamba I think?) which had no discernible latency and a nice dock for recharging the mouse, I was very happy with it until one evening it just stopped working. While alone in my flat, I stepped away from using my computer for about an hour, didn’t even put it to sleep, came back, and it would no longer move but would still register mouse clicks. I tried contacting customer support asking if there was a way to reset it or reflash the firmware or something and they’re just like “nope”. Last piece of Razer hardware I ever bought.

rufus_foreman 1y ago

Sometimes I think "Uncontrollable Urge" is the greatest Devo song ever. Other times, I think maybe "Jerk Monitor".

TheTon 1y ago

Several years ago, a coworker made an Arduino "mouse" that traced a square with a 1KHz report rate. Multiple systems running Windows 10 and reading mouse updates via either regular window events or the Win32 raw mouse API would occasionally lose events, meaning the square would drift over time. We tried both with a custom app and with drawing programs like Paint. We could not reproduce the issue on systems running macOS or Linux, and we chalked it up to a bug in Windows. It was hard to know if it affected real mice but I expect it did. I haven’t tried retesting with more recent versions of Windows to see if it is fixed, maybe it has been. Anyway, I’m not disputing OPs claim, I can totally believe it, but I always thought it was funny that pro gamers on Windows with high end mice could be losing the occasional movement and apparently nobody noticed that.