Re: Terminal Latency

On 2024-05-03, candycanearter07 <candycanearter07@...> wrote:

Interesting. I'm glad my terminal (urxvt) isn't too much slower than the
alternative.

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Glad urxvt is working for you!
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I think acceptable response time is a matter of taste.
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I've seen many comments from people who only use the terminal emulator
for system administration.  Most of their usage, uncluding editing, is
done in the GUI.  That's a whole different "use case" than running all
terminal-based apps and development tools.

I remember using 8-bit computers with video controllers and CRT's with
terrible refresh rates, flicker, etc.  My perspective is that it's all
good, even the worst case is better than that.
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Here's a comment from the original article:
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Generally speaking, there's a tradeoff between latency and
throughput/flicker.
 
The smaller the latency, the worse the throughput is (e.g. in cat
huge.txt) because the terminal has to render more frequently, and the
more flicker-prone it becomes, for instance when the terminal updates
the screen before the application completed its “output batch” - which
then requires another screen update once the output batch is complete,
e.g. when holding page-down in auto-repeat in vim or less.

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And here's a quote about latency from a different article:
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After thorough research on terminal emulators performance, I have come
to the conclusion that its most important aspect is latency.
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But what is latency and why does it matter? In his article, Fatin
defined latency as "a delay between the keystroke and corresponding
screen update" and quoted the Handbook of Human-Computer Interaction
which says: "Delay of visual feedback on a computer display have
important effects on typist behavior and satisfaction."
 
Fatin explained that latency has more profound effects than just
satisfaction: "typing becomes slower, more errors occur, eye strain
increases, and muscle strain increases". In other words, latency can
lead to typos but also to lesser code quality as it imposes extra
cognitive load on the brain. But worse, "eye and muscle strain increase"
seems to imply that latency can also lead to physical repetitive strain
injuries.
 
Some of those effects have been known for a long time, with some results
published in the Ergonomics journal in 1976 showing that a
hundred-millisecond delay "significantly impairs the keying speed". More
recently, the GNOME Human Interface Guidelines set the acceptable
response time (archive.org link, new hig guide has no guidelines) at ten
milliseconds and, pushing this limit down even further, this video from
Microsoft Research shows that the ideal target might even be as low as
one millisecond.

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<https://pavelfatin.com/typing-with-pleasure/>
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<https://books.google.com/books/about/Handbook_of_Human_Computer_
Interaction.html?id=WuQbERgXR10C&redir_esc=y>
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<https://en.wikipedia.org/wiki/Repetitive_strain_injury>
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<https://doi.org/10.1080/00140137608931531>
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<https://web.archive.org/web/20210306065942/
https://developer.gnome.org/hig-book/3.12/
feedback-response-times.html.en>
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<https://www.youtube.com/watch?v=vOvQCPLkPt4>