I think a lot of the time when people say the network is slow. They really mean their backend is slow.

With a fast backend ~1-5ms response times (not even that fast). Streaming compression over something like SSE to keep your response sub 1kb packet (roughly an ethernet MTU).

With a push based model, pushing data to a user is half their RTT latency. They will only experience their full RTT on actions they trigger.

Now the network to you is distance to the server (not your rail/nextjs backend taking 400ms). Things like 4G and 3G are fine. The real problem is when you have such bad signal you effectively have no down or up.

1-5ms response time is clearly hard for most real world endpoints.

I don't know how hard it is. But I can certainly say there is no business inscentive for it.

When it comes to improving performance by a few ms, or implementing a new feature, business people will always choose a new feature, unless the current performance is unbearably slow (we're talking regular 1.5s+ wait times for BE response).

And it's not even a modern problem, legacy software written 20 years ago has the same latency than most modern backends from my experience.

When I worked at Cisco we had regular 10 second responses on our main flows (bad data model) and still couldn't get buy-in to fix it.

> With a fast backend ~1-5ms response times (not even that fast).

Even though benchmarks suggest this sort of performance should be trivial, most real-world servers I have interacted with do not reliably managed to process a request, make a roundtrip to the DB, and return a response in <5ms

But why is that?

Project into sqlite on your app server is the main trick I use. Denormalize if you have to.

Hell, for a lot of projects you don't even need to get that fancy. Run a single server with an embedde database, running Go or Java and you're good to go.

Reddit's reaponses are rarely above 400ms. And yet their frontend routinely takes several seconds to render that response

How long the server takes to process the 42 requests ahead of you in line, or possibly how long the 318 poorly architected microservices take.

More to the point it's that the server has to retrieve and massage data from several docker services to retrieve the full context needed to process the request

A lot of that is ultimately ping time, too though. Like making a naive number of round trips to a database not on the same machine.