"
...for Massive Multiplayer Online Gaming (MMOG), real-time is a requirement.
As online gaming matures, players flock to games with more immersive and lifelike experiences. To satisfy this demand, developers now need to produce games with very realistic environments that have very strict data stream latency requirements:
300ms < game is unplayable
150ms < game play degraded
100ms < player performance affected
50ms > target performance
13ms > lower detectable limit
But this is real-time gaming. Typing should be less demanding, I'd think.
Edit: also https://stackoverflow.com/questions/536300/what-is-the-short...
Not really, unless you're the kind of guy working in Cobol and who is used to typing with latency.
I've seen Cobol developers just ignoring the latency, keeping typing because they know what they've typed and it doesn't matter that it's slow to show up on screen.
If the system works well, yeah, you can type all the stuff, then wait for it to show up and confirm. 'BBS mode' as someone mentioned.
I used to do that (not in COBOL), typing into a text editor in a terminal over a 2400-baud modem. Like the other commenter said, you get used to it, but it requires a certain predictability in your environment that you don't get in modern GUIs.
Anything below one frame (16.66ms) and whether or not any sort of real feedback is even received (let alone interpreted by the brain) becomes a probability density function. With each additional frame after that providing more and more kinesthetic friction until you become completely divorced from the feedback around 15-20 frames.
All of this means that the old figures are not useful as a rule of thumb unless your task is exactly what they studied. This paper notes how unhelpful that is with ranges from 2-100ms! They found thresholds around 25ms for some tasks but as low as 6ms for some tasks.
https://www.tactuallabs.com/papers/howMuchFasterIsFastEnough...
Keyboard latency is one of the harder ends of this spectrum: the users are focused, expecting a strong (high contrast, new signal) change in direct response to their action, and everything is highly trained to the point of being reflex.
When I’m typing text, I’m not waiting for the change to hit a key outside of games but rather expecting things like text to appear as expected or a cursor to move. Awhile back I tested this and the latency difference between VSC’s ~15ms key-to-character was noticeably smoother compared to 80+ms (Atom, Sublime) and the Citrix system I tested at 120-150ms (Notepad is like 15ms normally) was enough slower that it forced a different way of thinking about it (for me, that was “like a BBS” because I grew up in the 80s).
n.b. I’m not an expert in this but worked in a neuroscience lab for years supporting researchers who studied the visual system (including this specific issue) so I’m very confident that the overall message is “it’s complicated” even if I’m misremembering some of the details.
https://www.nngroup.com/articles/response-times-3-important-...
300ms would render most video games unplayable.
I see this claim a lot and it's making me want to build a website that gives you some common interactions (moving a mouse cursor, pressing a button) with adjustable latency so people can see just how big of an impact seemingly small amounts of lag have on how responsive something feels.
a) movies are not interactive so latency is not a concern, only fluidity is
b) movies come with pre-applied motion blurring to hide the low framerate (which is different from fake motion blur applied in some games)
c) 30 FPS is atrocious even for movies and I wish higher framerate movies had gotten more common
120ms end-to-end without Citrix would be quite achievable with many modern systems (older systems (and programs written for them) were often not powerful enough to do some of the things that add latency to modern systems). So if Citrix 120ms we already get up to your ‘not immediate’ number.
But I think you’re also wrong in that eg typing latency can be noticeable even if you don’t observe a pause between pressing a key and the character appearing. If I use google docs[1] for example, I feel like I am having to move my fingers through honey to type - the whole experience just feels sluggish.
[1] this is on a desktop. On the iPad app I had multiple-second key press-to-display latency when adding a suggestion in the middle of a medium-sized doc.
Personally I can get latency down to 200ms over the internet into a remote datacenter with WebRTC. The challenge however in practice is that running a CPU without a GPU will eventually starve the CPU because it has to do intensive things like run a 1080p video at 60fps which aren't feasible on a CPU only machine. This CPU load will then slow down the video encoder and overall responsiveness (no, responsiveness doesn't mean a mobile layout here) of the remote desktop.