[falcolas]

> paying through the nose for hardware in general

You also have to consider that there are limits to how parallel an application can be - Amdahl's Law - at some point even throwing hardware at a scaling issues has its limits.

Of course, there's also a truism that the team who implemented the first pass won't have to support (financially or as a developer) the software when it no longer scales.

[dnautics]

No, amdahl's law is (roughly speaking) a limit to how parallel an algorithm can be. Applications (in the sense of web apps) generally have the potential to scale via Gustafson's law, but we are (IMO) largely held back by framework and old ways of programming. https://en.wikipedia.org/wiki/Gustafson's_law

[falcolas]

So long as an application needs to share state between worker processes, (database, redis cluster, etc) then Amdahl’s law still applies. There’s very few modern applications that can truly scale linearly.

[imtringued]

You're confusing something. Fully consistent databases are primarily limited by the speed of communication because they need to replicate writes and queries to all nodes and wait for a response even if a node is on the other side of the planet. Unless your CPU is extremely slow (clock frequencies of a few kilo Herz) the speed of light is a significantly more important limit. This is actually a usecase where modern CPUs are more than fast enough and we don't need a significant improvement in processing speed. Faster storage and networks are welcome though.

[pdimitar]

As a guy using a 10-core Xeon workstation with 64GB 2666Mhz DDR4 ECC RAM and a NVMe SSD capable of 2.8 GB/s read and write... I have to tell you that I only partially agree.

I've noticed my compilation speeds got dramatically better (compared to a MacBook Pro and an old-ish i7-3770 desktop PC). And it can handle even the sluggishness of Slack just fine without you noticing a lag, which I view as a huge achievement.

However, one thing my very detailed system monitors are telling me every day is -- 99% of all software we use every day is not parallel enough. So I have this amazingly powerful CPU that only (1) Git garbage collection, (2) PostgreSQL restoring a big backup, (3) Rust compiler and (4) [partially] Elixir compiler can saturate to its full potential.

I'd say that if everybody buys the new AMD Threadrippers and PCIe 4.0 motherboards, RAMs, SSDs and GPUs, we'd all be collectively fine for like 10 years.

The software however, it badly needs more parallel processing baked in it.

[dnautics]

Share consistent state. Eventually consistent models (most web apps) are often generally okay.

[pdimitar]

(NOTE: I don't disagree with you, I am more like paraphrasing you and adding my take.)

In practice most software is light years away from this theoretical limit of "can't be anymore parallelised". And I fully agree that throwing hardware at a problem indeed has limits, although they are financial and not technical IMO.

As mentioned in another comment down this tree of comments, my 10-core Xeon workstation almost never has its cores saturated yet I have to sit through 5 seconds to 2 minutes of scripted tasks that can relatively easy be parallelised -- yet they aren't.

And let's not even mention how my NVMe SSD's lifetime saturation was 50% of its read/write limit...

There's a lot that can be improved still before we have to concern ourselves with how much more we can parallelise stuff. That's like worrying when will the Star Trek reality come to happen.