9 ms·

Is this an example of the kind of reactive, interactive design you're advocating? I don't see how this is helpful: it's dogmatic and doesn't address the actual

Is this an example of the kind of reactive, interactive design you're advocating? I don't see how this is helpful: it's dogmatic and doesn't address the actual tradeoffs that might be at play. Why 64 ms? And 32 and 16? What studies are you relying on to suggest that 65 ms is too slow or that 30 ms is too slow for initial feedback? How does it affect user behavior? What is advised when these rules, especially the "full screen of content" cannot be met because of things like external dependencies out of the site's control?

loup-vaillant 7y ago
60 frames per second. - 16ms: one frame - 32ms: two frames - 64ms: four frames So it's really 1, 2, 4. Maybe we could have 1, 2, 3, but I'm guessing the "48ms Manifesto" wouldn't sound too great: they probably preferred to have a nice power of two. And if I may, I think the manifesto is basically right. Something I have to wait several frames for before it reacts feels sluggish. When I type a character, I want it now, not 5 frames later. When I move the mouse, I want it in sync, not lagging behind my hand. Touch screens are even more exacting. They only feel perfect when latency falls under one millisecond. But that last one isn't achievable in practice on current stock hardware…
- userulluipeste 7y ago
  Well then... why 60 frames per second? This isn't obvious to me and I presume to others using today's tech too.
  - dvdkon 7y ago
    Because most displays today run at 60Hz. It's a nice metric, as it provides a useful coarseness for measuring response times.
dahart 7y ago
Yeah it's simplistic and doesn't explain the rationale, but having studied human perception a bit, I know without further explanation that this is targeting the time frames of our human ability to see change. The numbers here are similar to the reasons most movies are 24fps. > What is advised when these rules, especially the "full screen of content" cannot be met because of things like external dependencies out of the site's control? This is missing the point, and many people here seem to be attempting to pick the same nit. You never have to wait for external dependencies to show changes on screen. This is how browsers and well designed high traffic websites like YouTube already operate. When you take action, you are shown UI changes on-screen that indicate the action is in progress. The manifesto is saying to acknowledge the user action so the user knows the application received the request. It is not saying everything in the world needs to be done in 64ms. Applications can always acknowledge the request immediately, and yet some still don't.
- tedunangst 7y ago
  How can I show one full screen of content when it takes longer than 64ms for the content to get from there to here? An acknowledgment that the content is coming is not a screenful of content.
  - jlg23 7y ago
    64 ms East Coast to West Coast leaves about 20ms for content generation. That's plenty...
  - dahart 7y ago
    Instead of assuming that "content" must mean "network response", imagine some other possibilities. A full-screen gray-out box with a centered loading spinner over a YouTube thumbnail, along with the thin loading progress meter on the video's timeline is an example of a "screenful of content" that doesn't equate to the network response.
    - tedunangst 7y ago
      That a loading spinner would count as content is a sad commentary on how little value YouTube video content must have. :(
      - dahart 7y ago
        It seems like you're still having a hard time imagining what "content" might mean aside from the network response. In the context of a UI element or screen layout, "content" is the appearance of the UI elements on screen. The post, and my comment, isn't referring to web content or video content, it's referring to UI content. Twisting my words to comment on YouTube's quality is funny, but irrelevant to interaction latency.
- jlg23 7y ago
  > It is not saying everything in the world needs to be done in 64ms. Well, most actually could be. And a snappy "acknowledgement" only impresses me the first time. The second time I stare at the loading indicators in disbelief, while waiting for the not-so-snappy action to execute.
noobermin 7y ago
I don't agree with the page too, it seems better to make terms on order of magnitude may be (10s of ms, 100s of ms), but in their favor the exact times might not be hard limits but maxima in terms of latency, with the hope that you can be better. A point against me is specific numbers (ones that are essentially memorized by every programmer as powers of two) are easy to remember and good for messaging purposes.

loup-vaillant 7y ago

60 frames per second. - 16ms: one frame - 32ms: two frames - 64ms: four frames So it's really 1, 2, 4. Maybe we could have 1, 2, 3, but I'm guessing the "48ms Manifesto" wouldn't sound too great: they probably preferred to have a nice power of two. And if I may, I think the manifesto is basically right. Something I have to wait several frames for before it reacts feels sluggish. When I type a character, I want it now, not 5 frames later. When I move the mouse, I want it in sync, not lagging behind my hand. Touch screens are even more exacting. They only feel perfect when latency falls under one millisecond. But that last one isn't achievable in practice on current stock hardware…

userulluipeste 7y ago
Well then... why 60 frames per second? This isn't obvious to me and I presume to others using today's tech too.
- dvdkon 7y ago
  Because most displays today run at 60Hz. It's a nice metric, as it provides a useful coarseness for measuring response times.

dahart 7y ago

Yeah it's simplistic and doesn't explain the rationale, but having studied human perception a bit, I know without further explanation that this is targeting the time frames of our human ability to see change. The numbers here are similar to the reasons most movies are 24fps. > What is advised when these rules, especially the "full screen of content" cannot be met because of things like external dependencies out of the site's control? This is missing the point, and many people here seem to be attempting to pick the same nit. You never have to wait for external dependencies to show changes on screen. This is how browsers and well designed high traffic websites like YouTube already operate. When you take action, you are shown UI changes on-screen that indicate the action is in progress. The manifesto is saying to acknowledge the user action so the user knows the application received the request. It is not saying everything in the world needs to be done in 64ms. Applications can always acknowledge the request immediately, and yet some still don't.

tedunangst 7y ago
How can I show one full screen of content when it takes longer than 64ms for the content to get from there to here? An acknowledgment that the content is coming is not a screenful of content.
- jlg23 7y ago
  64 ms East Coast to West Coast leaves about 20ms for content generation. That's plenty...
- dahart 7y ago
  Instead of assuming that "content" must mean "network response", imagine some other possibilities. A full-screen gray-out box with a centered loading spinner over a YouTube thumbnail, along with the thin loading progress meter on the video's timeline is an example of a "screenful of content" that doesn't equate to the network response.
  - tedunangst 7y ago
    That a loading spinner would count as content is a sad commentary on how little value YouTube video content must have. :(
    - dahart 7y ago
      It seems like you're still having a hard time imagining what "content" might mean aside from the network response. In the context of a UI element or screen layout, "content" is the appearance of the UI elements on screen. The post, and my comment, isn't referring to web content or video content, it's referring to UI content. Twisting my words to comment on YouTube's quality is funny, but irrelevant to interaction latency.
jlg23 7y ago
> It is not saying everything in the world needs to be done in 64ms. Well, most actually could be. And a snappy "acknowledgement" only impresses me the first time. The second time I stare at the loading indicators in disbelief, while waiting for the not-so-snappy action to execute.

noobermin 7y ago

I don't agree with the page too, it seems better to make terms on order of magnitude may be (10s of ms, 100s of ms), but in their favor the exact times might not be hard limits but maxima in terms of latency, with the hope that you can be better. A point against me is specific numbers (ones that are essentially memorized by every programmer as powers of two) are easy to remember and good for messaging purposes.