This is a chart of latencies I created quite a long time ago, based on the best estimates I could find.

https://mikedilger.com/latency.html

Notice how slow the Internet is. Bandwidth has increased massively over the years, but latency hasn't because the distances haven't changed (except starlink is closer to earth) and the speed of light hasn't changed.

Notice rotational disks are also pretty slow, 10x faster than the Internet though.

Even SSDs and memory are slow compared to computations. You might be tempted to compute something once and save it to a variable, when in fact it might actually be better to just recompute it over and over in different places in your code. Compilers might improve this for you, or they might not.

What always seems suprising to me is that gigabit ethernet is 1000x faster to respond than your local physical disk! Writing to a server on your network is way faster than writing to a spinning magnetic platter in your local computer.

When writing rust, perfectionists worry about copying and memory allocation. These are the last things to worry about. I think they are useful to worry about, but you need to put it into perspective.

Compare their latency of memory allocation to that of contacting a DVM to sign your event for you. That latter having about 4 network round trips (DNS, SSL establishment, AUTH, and the request itself) takes something like 500,000 times longer. To get a better feel for that difference, if it takes 1 second to do a memory allocation, it takes on the order of 5 days to do a DVM request.