4 ms·

It's not just frame rate, but also input delay. If you're using Visual Studio Code, you might be used to waiting 100 ms for a character you typed to appear. My

It's not just frame rate, but also input delay. If you're using Visual Studio Code, you might be used to waiting 100 ms for a character you typed to appear. My personal workflow is based on Kitty and Neovim, which I've configured so that it can launch within 20 ms. Working without any input delay allows me to explore and edit projects at typing speed. As such, even tiny delays really bother me and make me lose my flow. I would believe Zed's focus on performance is motivated similarly. Also, I do not believe Windows on Arm64 is a very large demographic? Especially for developers, unless they're specifically into that platform.

breadwinner 1y ago
It is 18% according to this story: https://www.tomshardware.com/laptops/projections-show-that-arm-cpus-will-power-40-percent-of-notebooks-sold-in-2029 https://www.tomshardware.com/laptops/projections-show-that-a...
- kbolino 1y ago
  Most of that is macOS and ChromeOS, not Windows.
  - jsheard 1y ago
    Yeah. The Steam survey isn't a perfect sample since it's skewed towards gamers, but that currently shows just 0.08% of Windows users are on ARM, while 81.5% of Mac users are on ARM.
    - breadwinner 1y ago
      That may be true if you're looking at all windows computers in existence. If you look at new laptops being sold you see different numbers. As of 2025, Arm processors hold about 13% to 20% of the market share for new Windows laptops. This is important because these are the people who are more likely to download and install your software.
marcosdumay 1y ago
The only IDE I have used where frame rate is noticeable was Visual Studio (not Code). Once you are beyond a bare minimum, every other speed metric is more important. Zed does really well on many of those, but some depend on the LSP, so they become the bottleneck quickly.
adastra22 1y ago
You literally can’t tell the difference in a 20ms delay. That is an order of magnitude lower than the neural feedback loop latency. You may think that you can, but studies don’t back this up.
- poly2it 1y ago
  Do you not perceive more than 50 Hz?
  - adastra22 1y ago
    Do you react and respond per-frame of a video?
    - trenchpilgrim 1y ago
      Most people can with some Aimlabs training...
- trenchpilgrim 1y ago
  I don't have to think a full thought for every keystroke.
  - adastra22 1y ago
    Then you don’t have to have an input response latency so small as to be perceived instantaneously.
    - trenchpilgrim 1y ago
      I dunno what to tell you, Zed feels so much snappier than VSC to me.
- comex 1y ago
  Let's see. https://web-backend.simula.no/sites/default/files/publications/files/paper_6.pdf https://web-backend.simula.no/sites/default/files/publicatio... > At the most sensitive, our findings reveal that some perceive delays below 40 ms. However, the median threshold suggests that motorvisual delays are more likely than not to go undetected below 51-90 ms. By this study's numbers, 20ms is somewhat below the lower limit of ~40ms, but not too far below. 100ms would be easily perceivable - though, based on the other replies, it seems that VS Code does not actually have that much latency. Don't confuse this with human reaction time, which is indeed an order of magnitude higher, at over 200ms. For one thing, reaction time is based on unpredictable events, whereas the appearance of keystrokes is highly predictable. It's based on the user's own keypresses, which a touch typer will usually have subconsciously planned (via muscle memory) several characters in advance. So the user will also be subconsciously predicting when the text will appear, and can notice if the timing is off. Also, even when it comes to unpredictable events, humans can discern, after the fact, the time difference between two previous sensory inputs (e.g. between feeling a keyboard key press down and seeing the character on screen), for much shorter time differences than the reaction time. Of course, just because these levels of latency are perceptible doesn't mean they're a material obstacle to getting work done. As a relatively latency-sensitive person, I'm not sure whether they're a material obstacle. I just think they're annoying. Higher levels of latency (in the hundreds of ms) can definitely get in the way though, especially when the latency is variable (like SSH over cellular connections).
TiredOfLife 1y ago
> you might be used to waiting 100 ms for a character you typed to appear. The latest benchmark I could find is 2022 and it's nowhere as bad as you claim https://github.com/microsoft/vscode/issues/161622#issuecomment-1287528213 https://github.com/microsoft/vscode/issues/161622#issuecomme...
- dsissitka 1y ago
  I ran it on VS Code and kitty recently: https://news.ycombinator.com/item?id=45253927 https://news.ycombinator.com/item?id=45253927 https://news.ycombinator.com/item?id=45254054 https://news.ycombinator.com/item?id=45254054
  - TiredOfLife 1y ago
    Thanks. Could you please do Zed also? I tried, but it was struggling to type.
  - rs186 1y ago
    Did you run this on a clean VSCode install? I know as a matter of fact that bad extensions slow down VSCode significantly.

breadwinner 1y ago

It is 18% according to this story: https://www.tomshardware.com/laptops/projections-show-that-arm-cpus-will-power-40-percent-of-notebooks-sold-in-2029 https://www.tomshardware.com/laptops/projections-show-that-a...

kbolino 1y ago
Most of that is macOS and ChromeOS, not Windows.
- jsheard 1y ago
  Yeah. The Steam survey isn't a perfect sample since it's skewed towards gamers, but that currently shows just 0.08% of Windows users are on ARM, while 81.5% of Mac users are on ARM.
  - breadwinner 1y ago
    That may be true if you're looking at all windows computers in existence. If you look at new laptops being sold you see different numbers. As of 2025, Arm processors hold about 13% to 20% of the market share for new Windows laptops. This is important because these are the people who are more likely to download and install your software.

marcosdumay 1y ago

The only IDE I have used where frame rate is noticeable was Visual Studio (not Code). Once you are beyond a bare minimum, every other speed metric is more important. Zed does really well on many of those, but some depend on the LSP, so they become the bottleneck quickly.

adastra22 1y ago

You literally can’t tell the difference in a 20ms delay. That is an order of magnitude lower than the neural feedback loop latency. You may think that you can, but studies don’t back this up.

poly2it 1y ago
Do you not perceive more than 50 Hz?
- adastra22 1y ago
  Do you react and respond per-frame of a video?
  - trenchpilgrim 1y ago
    Most people can with some Aimlabs training...
trenchpilgrim 1y ago
I don't have to think a full thought for every keystroke.
- adastra22 1y ago
  Then you don’t have to have an input response latency so small as to be perceived instantaneously.
  - trenchpilgrim 1y ago
    I dunno what to tell you, Zed feels so much snappier than VSC to me.
comex 1y ago
Let's see. https://web-backend.simula.no/sites/default/files/publications/files/paper_6.pdf https://web-backend.simula.no/sites/default/files/publicatio... > At the most sensitive, our findings reveal that some perceive delays below 40 ms. However, the median threshold suggests that motorvisual delays are more likely than not to go undetected below 51-90 ms. By this study's numbers, 20ms is somewhat below the lower limit of ~40ms, but not too far below. 100ms would be easily perceivable - though, based on the other replies, it seems that VS Code does not actually have that much latency. Don't confuse this with human reaction time, which is indeed an order of magnitude higher, at over 200ms. For one thing, reaction time is based on unpredictable events, whereas the appearance of keystrokes is highly predictable. It's based on the user's own keypresses, which a touch typer will usually have subconsciously planned (via muscle memory) several characters in advance. So the user will also be subconsciously predicting when the text will appear, and can notice if the timing is off. Also, even when it comes to unpredictable events, humans can discern, after the fact, the time difference between two previous sensory inputs (e.g. between feeling a keyboard key press down and seeing the character on screen), for much shorter time differences than the reaction time. Of course, just because these levels of latency are perceptible doesn't mean they're a material obstacle to getting work done. As a relatively latency-sensitive person, I'm not sure whether they're a material obstacle. I just think they're annoying. Higher levels of latency (in the hundreds of ms) can definitely get in the way though, especially when the latency is variable (like SSH over cellular connections).

TiredOfLife 1y ago

> you might be used to waiting 100 ms for a character you typed to appear. The latest benchmark I could find is 2022 and it's nowhere as bad as you claim https://github.com/microsoft/vscode/issues/161622#issuecomment-1287528213 https://github.com/microsoft/vscode/issues/161622#issuecomme...

dsissitka 1y ago
I ran it on VS Code and kitty recently: https://news.ycombinator.com/item?id=45253927 https://news.ycombinator.com/item?id=45253927 https://news.ycombinator.com/item?id=45254054 https://news.ycombinator.com/item?id=45254054
- TiredOfLife 1y ago
  Thanks. Could you please do Zed also? I tried, but it was struggling to type.
- rs186 1y ago
  Did you run this on a clean VSCode install? I know as a matter of fact that bad extensions slow down VSCode significantly.