It's pretty obvious when using extended shortcuts or a string of keys that are committed to muscle memory, like Ctrl+Shift+P (+ first letter of a cmd) or Ctrl+K combos.
Imagine playing an instrument wired up to headphones and then adding a 30-60 ms delay... the longer the delay the more it creates that "off" feeling
Don't forget too, those are bare metal calculations. Stick those apps inside a VM like many devs do or add some other latency along the I/O chain and it all helps to create a perception of lag.
We need to keep these numbers in context. 30ms delay would appear as an echo if you were playing an instrument and also listening to a 30ms delayed version of the same sound.
However, you're not feeling the latency. You're noticing the presence of two distinct signals. That's why UX input latency matters much more when you're doing something like dragging across the screen with your finger on the screen: You visually register the distance between your finger and the expected location.
However, when you're typing a memorized series of letters on a keyboard, you're not comparing the keypresses to the letters appearing on the screen. You already know what you're typing and what you expect to see on the screen. Visual stimulus latency is on the order of 250ms, so you wouldn't even begin to start processing types for an order of magnitude larger than the latency of these text editors, for example.
Most of us are operating with regular 60Hz laptops or monitors. End-to-end latency from physical key press to physical color change on your monitor might be as high as 50-60ms even with zero-latency software.
nothing makes me want to throw my computer through the window faster than typing and not having an instant response honestly. It doesn't matter that the brain cannot process the letter. Would you imagine handwriting where the shape of the letters you write is 1/4th of letter shape late ?
Even for typing, just comparing xterm at 60hz and 120hz on my monitor feels different when typing moderately fast (100 wpm according to https://typing-speed-test.aoeu.eu/?lang=en)
Not necessarily; it could be an electronic instrument.
I once tested a "e-piano -> midi -> PC -> headphones" chain. The latency was not really noticeable when I pressed only a single key, but actually playing was impossible. After I replaced a (software) component with something with lower latency, it was bearable. While I cannot precisely estimate the latency reduction, I would guess that it was less than 30ms.
The eyes on the other hand have very little response to this. Some will say they can spot a 15ms vs 30ms visual delay easily, but this is an open debate rather than an obvious fact. A 15ms delay in audio is noticeable to almost anyone.
Different senses, different sensitivities. Comparing them isn't very instructive.
I've made a jumping mechanism for a game that makes you move faster if you jump right when you hit the ground again. This system does not give any audible cues as to when you should jump. When something in this system is slightly off, ie keyboard latency, jump height, gravity, etc. You can't time the jumps properly and you're left feeling that you somehow just can't do it but can't really pinpoint what the problem is exactly.
I think the same applies to many games. Especially fighting games.
With that said, I don't think writing code is about timing. I think it's nice when an editor feels very responsive, but I don't think it necessarily makes me more productive.
That is looking at the average latency for Atom. If you look at the max latency Atom, it is 60ms compared to 15 ms for Sublime text. That is basically 3 frames of latency difference on a 60Hz monitor, and would definitely be notable for the average person.
Having done some UX work in this area, I can say that people greatly overestimate the effects of latency on text entry when they're just looking at the numbers. End-to-end lag is more obvious in situations like dragging objects, but even then people manage to work around it.
Typing isn't performed on a tight feedback loop in the brain. We don't wait for the letter to appear on screen before starting the process to press the next key.
Typical human reaction types are on the order of 250ms for a simple visual stimulus. Recognizing letters will take even longer. A difference of a few 10s of milliseconds isn't generally going to be noticeable for typing unless you're really going to great lengths to A/B test.
Consider that people can SSH into remote machines all of the time with 100s of milliseconds of latency. The experience may not be optimal, but our typing doesn't fall apart over SSH.
I've experimented with video games with various amounts of display lag or dropped frames; nothing blinded or anything (although, setting up a blind test sounds fun), and there's clearly an increase in difficulty the farther you get between input and response. Writing code is clearly not Mario Brothers, but small delays can add up.
Indeed! I don't have a problem using say a SSH console with 1 second lag. After a bit of initial cursing, it works just fine, I can write my code or edit conf files just fine. It's not as comfortable as writing at home, but it's not really a big deal.
However if the lag is inconsistent, say due to packet drops, it's horrible. Even if the base latency is low.
You get latency-free editing because the file is edited locally and sent to the server on save. Simple implementation but highly effective.
This is more in the 1-2ms range, even for non-gaming devices.
Example: https://www.rtings.com/monitor/tests/inputs/input-lag (Scroll down to the non-gaming monitors)
The gray-to-gray response time for the physical pixels is in the neighborhood of 2-4ms, so the additional latency comes from the processing.
Example of a 9 year old "office" monitor: https://www.prad.de/testberichte/test-monitor-dell-u2412m/6/...
If you're using a 60Hz monitor, you're only going to see new frames every 17ms at most (1 second / 60Hz). Your graphics pipeline might have some additional buffering, adding 10s of milliseconds of lag. Your monitor likely has some input processing as well, adding anywhere from 10-20ms before it sends the frame to the physical display. Add a few milliseconds here and there for input processing and even the response time of the physical pixels, and you're looking at something like 50-60ms minimum for total display latency before you factor in the software.
Using 144Hz FreeSync or G-Sync monitors can shorten that update time, but you're still looking at 30ms end-to-end latency in even the fastest setups, and that's before you account for software processing lag.
The difference between Sublime Text responding in 11.4ms average and Atom responding in 28.4ms average is difference of almost exactly 1 frame of latency for a typical 60Hz monitor. Add up all of the other sources of lag (buffering, monitor input lag) and you're looking at something like a 5 frame latency instead of a 4 frame latency. Still less than the blink of an eye (literally).
From another perspective: If you really believe that you're sensitive enough to feel a difference between something like Sublime Text's 11ms processing latency vs. Atom's 28ms latency, then you might want to invest in a proper 144Hz gaming monitor with low input lag, as it would improve your experience by the same margins. A gaming-specific keyboard might also help, as average keyboards can have 10-20ms of input lag before the keypress registers with the OS (Source: https://pavelfatin.com/typing-with-pleasure/ ) Realistically, though, I doubt many people could A/B test the difference between a 1ms and a 30ms latency editor under ideal conditions, let alone while typing out some code.