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Comment by f311a | Hacker News Reader

Gamers are the biggest audience when it comes to high-end consumer CPUs. You don't need $550 CPU for your laptop or PC if you don't play games.

Many professionals, including developers, don't need such CPUs too.

When I need a lot of CPU power, I just ask my company to provide me servers.

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>>Many professionals, including developers, don't need such CPUs too.

Lol, sorry, but our C++ projects have an average build time of 40 minutes on an 8-core/16threaded Xeon CPU in my workstation. Even using Fastbuild/SN-DBS it still takes 5-10 minutes. We'll take any number of cores we can get, thank you.

I wasn't familiar with Fastbuild or SN-DBS. Can/should they be used in conjunction with ccache?

Yeah, but there are 10 JavaScript developers for each C/C++ developer.

I'm a Python developer and I can work from laptop. I do a lot of data processing and my laptop can handle development and testing. On production, some of the scripts are running on 64 core machines and use vector operations via numpy and scipy.

Even JS devs “compile” their code and use multiple threads. And when JS runs, every JS engine uses multiple threads (parsing, running, GC). Just look at how many threads chrome is using on a single web page. No need to throw shade on JS devs and their equipment needs.

Yes, but you can't use 105W CPU in your laptop anyway.

In a company where I work, almost every front-end developer uses a laptop with an external display because it's a portable solution.

I don't know if you can use it, but you sure can buy it: https://www.originpc.com/gaming/laptops/eon15-x-amd/

Sure, there's also a company called Eurocom which will happily stick a 165W nominal TDP Intel CPU into a laptop case - but there is no way it can run at maximum boost for a very long time.

I think OP's main argument is that if you actually need a lot of cores, then you should probably be offloading some of that work onto a server.

I currently use a 6-core mobile H-class CPU for my work that is a mix of Java and JS development, with a bunch of browser tabs and docker containers running, large IntelliJ project, etc. While my system often has a lot of processes/threads running, the main cost of those is in memory utilization rather than constant CPU performance.

I'm not saying that can't use more CPU horsepower, but it's certainly enough for my needs (for now). The main benefit of having more cores for me right now is just to maintain system responsiveness while running a bunch of background tasks, rather than raw throughput of large compile jobs.

Kind of the same setup for me. Primarily Java work on a 6 core laptop. Between Chrome absurd RAM/cpu usage, IntelliJ, Gradle, Weblogic memory usage is just super high and cpu is not so little either at times even without build. Add anything extra I'm running for diagnostic, performance tuning and things are very troublesome. And Mac doesn't seem to handle such pressure as gracefully as Linux (though I'm not 100% sure).

I'm running Linux and things generally feel pretty smooth to me. It wouldn't surprise me if Linux had better multi-tasking support.

I think more than better multi tasking it's handling of load when things are at the limit in some fashion whether is excessive cpu or ram.

LOL I'm a "js developer" and the system I work on requires like 10 docker containers. Not sure where this idea comes from that JS developers don't need power.

Webpack compilation of hello world projects are insanely long task. If new CPU can reduce this *hit in 20% I will be happy

But if people switch to those better CPUs, they will make the compilation even more complex... we just can't win the battle with bloated software.

None of the main platform client dev tools are lightweight. Xcode and Android Studio are massive and super complex, not just Webpack. Client dev isn't as simple as we like to pretend.

You are just wasting cycles and memory. Don't use docker if you care about performance.

This kind of response is supremely unhelpful. I work at a company with a large team, I'm not just going to tell all 300+ people to drop everything and rewrite the entire dev stack. Docker has become the de facto standard for dev environments.

My comment was flippant because your comment was useless. Of course if you decide to use something like docker you will force yourself into a performance corner. This would happen with literally any piece of software. It's not then valid to use that as a way of requiring a better cpu. No what you need is to get your development environment in order.

Btw docker is only standard for CI systems. Never would I advise anyone to actually use docker for local development let alone 10 docker instances at once. It's just pure insanity.

Why is it not valid to buy a better cpu to have a better dev environment? What does validity even mean here? I was never told I had to check in with you when making decisions. Before docker I remember spending tons of time setting up dependencies locally on machines when starting a new job, or maintaining puppet scripts to do so. And then since machines change over time, and run a different OS, your dev environment never quite matches prod. A $500 CPU is drastically cheaper than the bugs, headache, and time suck of maintaining a dev env.

Of course you can buy a better Cpu. It's not a valid argument in this context. The OP was talking about needing a better CPU because his large C++ project takes a lot of time to compile. That's something inherent to C++ programming. You then make the argument that js devs also require better CPUs because your js project use 10 docker instances. That's not valid logic since docker and js have nothing to do with eachother.

There are many alternatives to docker which don't cripple your computer. Nix is the best one.

FYI, your objections here don't make sense. Developers of any kind can benefit from better horsepower.

Whether it's having to run a lot of Docker containers, a large C++ project, or a large Webpack project.

Nitpicking and criticizing someone's dev environment is irrelevant.

If you don't like their example, I'm working on a JS project where I run a lot of local VMs to locally test the web client in different configurations. It would continue to be a bizarre response if you thought it was time to tell me to "just use browserstack.com" or something. Software isn't as easy as we think.

You misunderstand what I said. I didn't say any developers won't benefit from having a better CPU. What I disagree with is the statement that JS developmant is comparable in this way to C++ dev. In C++ dev the required horsepower is INHERENT because of the language. This is simply not the case for JS development. If you require high horsepower for JS dev it's because you work in a dev environment that results in requiring that horsepower. It is a CHOICE someone made when setting up the dev environment. That same choice could be made for any dev environment and doesn't have much to with JS.

With modern JS toolchains, arguably JS devs care more about top single core perf than C++/Rust/Java devs.

> 8-core/16threaded Xeon CPU

What generation and what frequency?

Those things can be quite dissapointing for what they cost compared to consumer CPUs.

I would expect the 5950X to be around 3-6 times faster than an 8 core Xeon.

It's the Xeon W-2145.

I have the iMac Pro with the Xeon W-2150B and I definitely expected more compilation speed.

It's fast, sure, but for that price tag I expected more. Currently evaluating buying a TR 2950x workstation. That seems to be amazingly fast though my research on the net is still ongoing.

"Any number of cores" != "Fastest possible core design"

I also compile large, multi-compilation-unit C++ programs, and it's much, much better to have a 24 or 32 threads clocked at 2 GHZ than 8 threads clocked at 5 GHz.

The parent comment was talking about fast individual core designs, which are genuinely useful for gaming, and can't be approximated by adding more cores.

Been a long time since I've done heavy C++ development (long time) but how does Fastbuild compare to Incredibuild?

It's about the same, we've stopped using Incredibuild some time ago because there were almost no benefits to it over Fastbuild and the cost was huge.

20% faster CPU isn't going to solve your problem. You should look into caching and distributed compilation.

The biggest companies in the world writing the largest software don't have build times that slow.

Uhm, yes they do? And I did mention Fasbuild and SN-DBS?

If you compile large c++ codebases they are a godsend. A slide showed 5950x was only 9% better at a compiler benchmark than the 3950x though. A deeper pipeline based IPC increase may suffer with missed branch prediction in the type of parsing and optimizing workloads of compilers and not get the full benefit.

Do C++ developers prefer desktop computers at work? I think a lot of them use laptops.

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.

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

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

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.

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?

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.

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.

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

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

Yeah I noticed that comparison and was surprised at that given the amazing single thread benchmark performance improvement. We really have to see the benchmark.

One might end up in a situation where for developers the older generation cpu being cheaper and more available might make more sense.

I wish somebody really did some suitable benchmark suite for developers.

You don't want older generation CPU. You won't clean/build your project after every change. You'll use some kind of incremental build which will use few cores. Your IDE will use few cores. And significantly faster single-thread performance from new generation will be extremely helpful.

Do have to wonder if 5950X is that much better than 5900X in GCC?

It should be: all the way up to the 64 core threadripper scales pretty linearly for compiling. It probably won't be worth it over whatever the 3950X price drops to though, if per-core performance is really only 9% better in compiling workloads.

I mean more in price to performance. Will +200 dollars be worth the lower base clock and increased core count?

11% lower base clock, 33% more cores. The 5950X also has 100% more L3 cache.

> Many professionals, including developers, don't need such CPUs too

While I agree that many people don't need mass multi-threading, I don't count developers among those.

Compilation and transpiration are computationally intensive, and usually take advantage of multi-threading. Developers often also run multiple virtual machines and containers, for example to run a database, message bus or blob store.

As a developer, I'll take all the compute capacity I can get, thank you very much!

Apparently you don't do development, local virtualization, work on enterprise apps, or any of 1000s of other things that benefit from extra horsepower

They said biggest audience, not the only one.

I definitely need ram way more than I need CPU, but there are still plenty of things that CPU helps me save time with as a dev, and often those things are somewhat parallel. So more cores is good too.

> Many professionals, including developers, don't need such CPUs too.

True, though I think there's a distinction between "need" and "can make use of". If I'm going to spend 8+ hours a day working on a computer, I'd probably be willing to spend a extra 20% or whatever on total system cost to eek out a bit extra performance even if that cost doesn't make sense from a strict cost/benefit calculation.

That said, there isn't really a good way for developers to calibrate the hardware to their workload.

It's not that developers don't need these CPUs, it's just that there's a lot more gamers than developers, and most of them will buy laptops or be provided workstations with Ryzen PRO or Threadripper processors.

You don't need it if you DO play games. I'm running an 11 year old Xeon, that maxes every modern game at 2560x1600 on a 1070. GPU is WAY more important than CPU in gaming.

> GPU is WAY more important than CPU in gaming.

depends on the game. plenty of popular esports titles will bottleneck on the CPU with even a low end graphics card.

Look at any gaming benchmarks, unless they are running them at low resolutions, the CPU is not the bottleneck. I agree there is some fringe simulation cases, but most gaming is not inhibited by CPU. Once you're up in the 2k and 4k land, the GPU is the bottleneck. This video focuses on 1080p performance benefits. There is zero reason to be upgrading between generations unless you're just burning money. Anyone paying $500+ every time there is a new CPU platform, is guaranteed already running 2k and 4k content.

Simulation is not necessarily 'fringe'. Kerbal Space Program, Oxygen Not Included, heck... Dwarf Fortress (ok, the last one IS fringe).

You are correct that most games don't use that much CPU. Most titles will run comfortably with an Intel I3 from the past three generations or so, provided there are no bottlenecks in the GPU. The CPU will be the bottleneck, but if you are getting sufficient framerates, so what?

Modern CPUs are insanely powerful. Even then, I moved to Ryzen - for the above mentioned titles.

I run Kerbal and Dwarf Fotress on an 11 year old Xeon, as well as every other modern game with a 1070 at 2560x1600. All the eye candy on. I'm not suggesting running a decade old CPU, but it's completely silly for this presentation to be pumping expensive CPUs for 1080p gaming benefits.

The reason why they ran the benchmarks at 1080p is because they want to ensure they are not GPU bound.

I don't disagree with you but I think this AMD video focused on closing the gap with Intel's single-core performance -- and many games are still single-core.

I upgraded for Crusader Kings and, especially, Stellaris on large galaxies. Simulations are a great example of needing CPU.

it's really not so clear cut outside of the few highly gpu-intensive AAA titles that get released each year. I play csgo (an older, but still very popular game) on a 4k display. my gpu hovers around 40% at max settings, while a couple cpu cores are constantly pegged.

it is hard to find benchmarks to show this however. the reputable sites mainly focus on 1080p because this is where the difference between cpus is most visible. doesn't mean there isn't a meaningful difference at higher resolutions, it just isn't as good a way to show what they are trying to show in a cpu review.

> There is zero reason to be upgrading between generations unless you're just burning money.

agreed, the speedup is almost never worth such a short upgrade cycle, especially for consumers. but this is moving the goalposts given the thread's context.

https://www.youtube.com/watch?v=dmeWo7BLN9Y According to DF, 4k games are bottlenecking on the CPU via the 3090

When do they say that in the video? The CPU-limited comment at 10:28 is for 1080p / 1440p.

10:41 , so 10 more seconds. I910900k bottlenecking Hitman 2 at 4K Max

It doesn't seem like that's 4K: the text on the top-right corner clearly says 1080p or 1440p next to each framerate. The narrator also says 1080p and 1440p.

It's definitely confusing, since there's a mention of 4K elsewhere...

Sure, but that drives the point further right? Already CPU bound at 1080P

not really. cpu bound at 4K implies cpu bound at 1080p, but the converse is not true.

No. The CPU is the bottleneck at 1080P, but the GPU might become the bottleneck at a higher resolution.

While I agree with the general statement, I want to remark that 1080p is actually 2k if you treat 2160p as 4k.

I guess you mean 1440p - which you could maybe label as 2.6k. But I don't think there is any such designation. Calling it WQHD is probably the right thing.

The big CPU-bottlenecked esports game is CS:GO, or any other Valve / Source game. Even on an older CPU with mediocre single-threaded perf (i7-5820K), I can run the game fine on high settings, 1080p (100-250fps), but it occasionally dips down below my 144hz refresh rate, which can be annoying.

And yeah, the GPU is never begged while playing, but multiple CPU cores definitely are.

Also, emulation is another big place where CPU bottlenecking is a thing. Look at Dolphin (Gamecube/Wii), Citra (Wii U), and yuzu (Switch), they're all CPU bound. Folks in the various subreddits will ask why their new GPU isn't netting them a higher framerate, and it's because the GPU is almost not even used (though in some cases with better graphical effects, shaders, etc. they can be beneficial)

It depends. I threw together an HTPC a few months ago out of mostly second-hand parts and it's been a mixed bag. With an i5-4460 and an RX 570, I can run modern shooters perfectly, but a bunch of indie games give me unexpected trouble. Hades for example (isometric roguelite heavy on visual effects) still gives me lots of slowdowns and framedrops, and I even get jitter and issues on some really old titles that I would have expected to be butter-smooth, like Sonic Generations.

The RX 570 is definitely a budget level GPU, an upgrade to that would certainly give you what you need to run those games on an I5 properly.

Sure it's a budget card, but I don't think it's the issue, because I got great performance on COD WWII (2017) when I tried it at 1080p on high settings.

Additionally, the games listed as problematic ran great on a Dell laptop equipped with an 8th-gen i7 and a GTX 1050 mobile. At least, they ran great for like a minute or two until the thermal throttling kicked in. So given that my HTPC build does have issues, and it has a slightly better GPU and much worse processor, I'm inclined to think the processor is the problem.

Unfortunately, I don't think there's much point trying to get a better processor than that for the old LGA 1150 board, when I could spend only slightly more cash on some DDR4 RAM, a B450 motherboard, and maybe an older Ryzen to be upgraded to one of these Zen 3 ones in a few years when prices have dropped.

Have you tried MS Flight Sim? That's the game that convinced me it's time to upgrade my trusty i5-4670k

If you're playing at high framerates (120Hz+) you'll find that your CPU is inadequate for many recent games.

(playing games on a 1070 and a 6 year old Xeon and feeling the lack of single-threaded performance)

Not for content creators and other workstation type applications - all those non server workstation boards are going some where right?

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