5 ms·

Missing rows in the tables are human reaction time (~250 ms) and human perceived-as-instantaneous time (~100ms). Beyond a lot of wasteful programming, we also

by gok 9y ago

Missing rows in the tables are human reaction time (~250 ms) and human perceived-as-instantaneous time (~100ms). Beyond a lot of wasteful programming, we also understand better today what we are engineering for than we did in 1977.

mrob 9y ago
>human perceived-as-instantaneous time (~100ms) Nonsense. You can test this yourself. Open a fast terminal, eg. xterm (libvte based terminals have a low framerate and are unsuitable). Try: sleep 0; echo "test" sleep 0.05; echo "test" The difference is immediately obvious.
- fred256 9y ago
  Also, it's immediately obvious to anyone who's ever ssh'd to a server on another continent. The added ~100 ms latency makes for a very different "feel".
- gok 9y ago
  That is describing a different issue. This test shows your visual system can detect the difference of 50ms between animations. Indeed, the human visual system can also tell the difference between 60 FPS (16ms) and 120 FPS (8ms), and even higher! This doesn’t mean that you can tell the difference striking a key and seeing the character draw on the screen after 8ms instead of 16ms.
  - feanaro 9y ago
    Typing (i.e. pressing many keys in sequence instead of only a single key) could then be interpreted as animation, which by this logic would make such a difference in latency detectable again.
Razengan 9y ago
A latency of 100ms in online games is definitely not perceivable as “instantaneous.”
sowbug 9y ago
I don't believe these metrics, because I can certainly tell the difference between a 10ms ping and a 60ms ping in an online game. Yet there is this cat in my neighborhood that makes me think I'm deluding myself, and that I'm actually a quarter-second behind the real world. It is a long-haired black cat. It doesn't like us. But it does like taking a shortcut through our front yard. If it sees us, it freezes. It waits, mid-stride. Then when it's satisfied we're not a threat, it starts moving again. If I move my arm or shift my body, it freezes again, sizing me up, sure that this is the day -- after all these years -- that I'm finally going in for the kill. What's weird is I am convinced that this cat knows when I'm going to start moving. It halts before I move. By the time my head is moving or my arm is waving, it is already frozen and on high alert. My working theory is not that this cat is telepathic or that it has defocused temporal perception. Rather, I think that because the cat is smaller than I am, its eyes are closer to its brain, its nerve impulses don't have to travel as far, and it really and truly knows before I do that I'm moving. Otherwise I can't explain this cat's superhuman reflexes or its blatant disregard of general relativity.
- adrianN 9y ago
  Did you ever touch the cat? Can other people see the cat too?
  - shellbackground 9y ago
    Did you show this story to different people? Can other people see that different people?
    - mcguire 9y ago
      I, for one, do not actually exist. Sorry.
- baddox 9y ago
  Cats are certainly known to have good reflexes.
- Izkata 9y ago
Veedrac 9y ago
~0.1s is the limit after which there is a distinct delay between action and response. This is not the same as the point at which things feel instantaneous. > 0.1 second: Limit for users feeling that they are directly manipulating objects in the UI. For example, this is the limit from the time the user selects a column in a table until that column should highlight or otherwise give feedback that it's selected. Ideally, this would also be the response time for sorting the column — if so, users would feel that they are sorting the table. (As opposed to feeling that they are ordering the computer to do the sorting for them.) https://www.nngroup.com/articles/powers-of-10-time-scales-in-ux/ https://www.nngroup.com/articles/powers-of-10-time-scales-in...
- gok 9y ago
  I’m not denying that. I’m saying that anything over 100ms is meaningfully deficient, and anything under that is nice to have but not distractingly bad.
  - mcguire 9y ago
    ... for single events.

by gok 9y ago

mrob 9y ago

>human perceived-as-instantaneous time (~100ms) Nonsense. You can test this yourself. Open a fast terminal, eg. xterm (libvte based terminals have a low framerate and are unsuitable). Try: sleep 0; echo "test" sleep 0.05; echo "test" The difference is immediately obvious.

fred256 9y ago
Also, it's immediately obvious to anyone who's ever ssh'd to a server on another continent. The added ~100 ms latency makes for a very different "feel".
gok 9y ago
That is describing a different issue. This test shows your visual system can detect the difference of 50ms between animations. Indeed, the human visual system can also tell the difference between 60 FPS (16ms) and 120 FPS (8ms), and even higher! This doesn’t mean that you can tell the difference striking a key and seeing the character draw on the screen after 8ms instead of 16ms.
- feanaro 9y ago
  Typing (i.e. pressing many keys in sequence instead of only a single key) could then be interpreted as animation, which by this logic would make such a difference in latency detectable again.

Razengan 9y ago

A latency of 100ms in online games is definitely not perceivable as “instantaneous.”

sowbug 9y ago

I don't believe these metrics, because I can certainly tell the difference between a 10ms ping and a 60ms ping in an online game. Yet there is this cat in my neighborhood that makes me think I'm deluding myself, and that I'm actually a quarter-second behind the real world. It is a long-haired black cat. It doesn't like us. But it does like taking a shortcut through our front yard. If it sees us, it freezes. It waits, mid-stride. Then when it's satisfied we're not a threat, it starts moving again. If I move my arm or shift my body, it freezes again, sizing me up, sure that this is the day -- after all these years -- that I'm finally going in for the kill. What's weird is I am convinced that this cat knows when I'm going to start moving. It halts before I move. By the time my head is moving or my arm is waving, it is already frozen and on high alert. My working theory is not that this cat is telepathic or that it has defocused temporal perception. Rather, I think that because the cat is smaller than I am, its eyes are closer to its brain, its nerve impulses don't have to travel as far, and it really and truly knows before I do that I'm moving. Otherwise I can't explain this cat's superhuman reflexes or its blatant disregard of general relativity.

adrianN 9y ago
Did you ever touch the cat? Can other people see the cat too?
- shellbackground 9y ago
  Did you show this story to different people? Can other people see that different people?
  - mcguire 9y ago
    I, for one, do not actually exist. Sorry.
baddox 9y ago
Cats are certainly known to have good reflexes.
Izkata 9y ago

Veedrac 9y ago

~0.1s is the limit after which there is a distinct delay between action and response. This is not the same as the point at which things feel instantaneous. > 0.1 second: Limit for users feeling that they are directly manipulating objects in the UI. For example, this is the limit from the time the user selects a column in a table until that column should highlight or otherwise give feedback that it's selected. Ideally, this would also be the response time for sorting the column — if so, users would feel that they are sorting the table. (As opposed to feeling that they are ordering the computer to do the sorting for them.) https://www.nngroup.com/articles/powers-of-10-time-scales-in-ux/ https://www.nngroup.com/articles/powers-of-10-time-scales-in...

gok 9y ago
I’m not denying that. I’m saying that anything over 100ms is meaningfully deficient, and anything under that is nice to have but not distractingly bad.
- mcguire 9y ago
  ... for single events.