We are a company that only does development in C++ and everyone has a desktop workstation. Laptops are simply too slow unless absolutely huge and besides my minimum requirement in a workstation nowadays is 64GB of ram with 128GB preferred. Hard to find a laptop that can support that much.

Honest question, why no build farm?

We have a build farm. This is just for running the editor.

Why does it need that much?

Because the data it loads is about 40GB in size? If I then want to actually run locally built client, then it very easily hits 128GB. Games development :P

My MacBook has 64, don’t think 128 is an option.

You can always get roughly 2-3x the CPU performance of a laptop in a desktop (2x core count, higher clock due to much bigger heatsink). It makes sense to use a desktop for the compile times.

The most performance you can get in a mobile CPU right now is an 8 core ryzen. On a desktop you can get the 3990x at 64 cores. That's at least 8x the performance.

Can't fit a 32 core threadripper in a laptop no matter how hard you try. Afaik most use workstation desktops if they're working on large codebases with long compile times (think chrome, Firefox, unreal engine, etc. with compile times often in the hours on slow computers).

I usually find myself developing C++ code directly on servers, via SSH. In that setup, a laptop + external monitor is my preference, because of portability.

If I ever get to do local-machine development again, the choice of laptop vs. desktop really depends on how build times compare, and which platform has Intel CPUs with the required ISA extensions.

Which ISA extensions are useful for compilation?

None really, compilation is considered a branch/integer workload and has been that way for decades. Its a lot of tree traversals, and short string manipulation. One of the bigger boosts in recently memory were the "fast strings (rep mov*)" implementations about 10 years ago.

Single core compilation is actually a fairly good metric for general purpose performance. Of course it scales almost linearly with core count too.

Regarding the speed of compilation, I'm not sure which if any recent ISA extensions matter.

What matters to me is the ISA extensions that are needed by the software I'm building, typically DL or HPC code. Life is easier when I can build and test the software on my local machine, without having to involve some fancy new server.

Many of us who do use laptops do the builds elsewhere.

depends on the project. it takes me about 20 minutes to do a full build on an overclocked 9700k. if I were forced to use a laptop, I would probably quit.

What about spinning up a 24core vm and mount your code with sshfs for those compiles? Edit: corrected ashes to sshfs

this has been discussed internally. for a variety of reasons, testing the software on a remote machine is kinda painful, so we would still have the overhead of copying the executable back to the developer's machine. the more straightforward approach is just to buy fast desktops for all the devs. a desktop with 32GB ram, a top of the line consumer cpu, and a middling gpu is roughly the same price as a good ultrabook anyway.

also, c++ compilation doesn't scale perfectly with more cores. linking is still single threaded, AFAIK.

lld will parallelize your link step. Major improvement over ld. Barely any change to the rest of your build process.

Have you tried it with a Rust project? Is there a real gain? Really curious and willing to try.

sshfs adds far to much latency to large compiles which tend to open a ton of little files, read a KB or two, and close them. If your on a local LAN its doable on NFS or other low latency network sharing, but for everything going over the internet ssh is going to be far to slow. In those cases its better to just git pull the changes and maintain a local copy on the compile target.

What do you mean? The code is on the build server. You only need to push your human-timescale changes.

Is DistCC (or related tech) not a thing anymore?