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Transatlantic ping faster than sending a pixel to the screen? (2012)

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Re: Transatlantic ping faster than sending a pixel to the screen? (2012)

#3
post #2

This is a classic and wonderful way to learn and think about the junction of physics and computers. Another one is https://news.ycombinator.com/item?id=702713

Gosh that's a fun read in all sorts of ways. SSDs are relatively new, there are hold-outs, and they cost $300 for 80GB!

Re: Transatlantic ping faster than sending a pixel to the screen? (2012)

#6
post #2

This is a classic and wonderful way to learn and think about the junction of physics and computers. Another one is https://news.ycombinator.com/item?id=702713

Imgur has has become so horrible that it loaded all recommendations first and it had still not loaded the main content before I closed the tab. I wish this was hosted somewhere else.

Re: Transatlantic ping faster than sending a pixel to the screen? (2012)

#7
post #2

This is a classic and wonderful way to learn and think about the junction of physics and computers. Another one is https://news.ycombinator.com/item?id=702713

Imgur has has become so horrible that it loaded all recommendations first and it had still not loaded the main content before I closed the tab. I wish this was hosted somewhere else.

Never loaded for me. Alternate site: https://ibb.co/HHgRSG8

Re: Transatlantic ping faster than sending a pixel to the screen? (2012)

#8
I have always been crying about latency computing for years. My earliest HN comment on the topic was in 2012. And I have been ranting about it for even longer outside

I really hope at the later part of this decade we start focusing on latency computing instead of bandwidth. From Display, Input, Output and Network, and down to OS and Software. I had always hoped VR would forced those optimisation due to VR being a latency sensitive, as John Carmack was doing at the time. But VR never happened.

Re: Transatlantic ping faster than sending a pixel to the screen? (2012)

#9
Optimizing for latency is often counter-intuitive.

Polling as an example may be an effective way to lower latency, e.g. Linux NAPI.

Increasing buffer sizes may also decrease latency because data can be processed in bursts, see buffer starvation. But if data comes in at a higher rate than can be processed, buffers fill up and are horrible for latency.

Re: Transatlantic ping faster than sending a pixel to the screen? (2012)

#10
The transatlantic ping is waves traveling at the speed of light in fiber and a large fraction of the speed of light in copper. To send a pixel to a screen you need to wait for the next vsync if you're not using a variable refresh rate display. That alone can be double digit milliseconds. Then you need to wait for the crystals in the screen to physically move in response to applied voltage. Moving things is slow. Moving things happens at speeds far less than the speed of light unless you're putting in enough energy to vaporize a city.

If you wait around and rely on things that move extremely slowly compared to the light speed of fiber and near light speed of electrical signals, waiting around for a crystal to turn and align itself to a voltage is going to take an eternity in comparison.

So yeah, no shit it's slower to display a pixel.

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