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> Why aren't we seeing 8, 16, 32 and 64 cores?

Intel has 8-core i7s, up to 18-core Xeon processors, and up to 61 cores in Xeon Phi coprocessor packages.

> If you reduce the feature size and effectively thus double the surface area available, why not increase the cores?

Because, outside of narrow domains, software that can effectively use lots of cores doesn't exist, so you don't provide good bang for the customers buck by doing that. For most customers, there's no utility for that.

> Cache can improve performance but not like more cores.

And vice versa -- more cores can improve performance, but not like cache. Which is more useful depends on software and workloads.

> Under Erlang/Elixir, we are able to get close to linear speedup from additional cores.

On the right kind of workloads. And, the people with those kind of workloads, have many-core processors available.

Any web server that serves at scale can readily use 1024 cores... Nginx, servers built in Go, Erlang and many more. It would reduce hosting costs and complexity substantially.

Lets say, for the sake of argument, that's true; what percentage of computers are "web servers that serve at scale". What's the cost of setting up production lines for 1024-core chips for just that market -- and how many chips are you going to be able to amortize that cost over.

Even if it was possible, I think the costs would be exhorbitant, even if the marginal cost per chip wasn't.

It's not as easy as you seem to think to e.g. (de-)multiplex a single TCP port to/from 1024 cores, and that's before you actually try to keep any application state in sync. Lots of stuff breaks at that level of concurrency.

First part makes sense, but the last part doesn't. Keeping application state in sync doesn't need to affect the throughput of events coming out of a multi-threaded application.

Those servers are also typically not CPU bottlenecked and while they would have 1024 threads (or even vastly more) they don't really benefit from 1024 cores.

Further, we're in an industry of VPSes where cores are virtualized and divided up. a 128 core CPU could produce 128 single core VPSes with probably better performance.

Of course this is consistent with your point, but your comment is negative, as is my parent comment.

Substantive discussion is not appreciated on hacker news.

More cores is always a good choice for consumer chips - even if one program doesn't effectively use them, running multiple applications in parallel sure as hell does.

And these days, we're running everything under the virtual sun and expect it to work fast and smooth :-)

Two things I can think of: for consumers, applications don't currently make the best use of multiple cores. There just isn't enough work to do on them. For gaming at least, DirectX 12 will remove a limitation that only one CPU core can control the GPU at a time. That may push demand for more cores upwards over time.

Second is that cache coherence gets really ugly the more cores you have with a single shared memory. From what I understand, this is a limitation of assumptions in the x86 architecture. A completely new architecture might sidestep the problem, and indeed I've heard of 1024 core machines etc, which I doubt have just brute-forced cache coherence.

DX12 - catching up to Mantle and Vulcan but ahead in marketing.

for desktop systems, small number of fast cores is still better than multiple slower ones, since a lot of the software that would profit most isn't very well optimized for making use of many cores. IMHO there is not that much demand for better performance in bread-and-butter CPUs anyways, things like embedded graphics, power saving etc matter more.

The top desktop CPUs have 6 or 8 cores, and Intel Xeons go up to 18.

And there are the Intel Xeon-D and Atom Cxxxx, which go in the direction of having (at the moment up to 8) smaller cores and low energy usage, for tightly packed servers and networking devices. I guess once they get more established they might get higher-power counterparts with more cores.

And the Xeon Phi might get there, if Intel manages to do what they promise for future generations.

> each core seems to grow to fit the available space, with only adding a few instructions, which only add marginal utility. Not the same as doubling the number of cores, which would double theoretical performance.

The progress between generations isn't big enough to allow doubling the core count in the same envelope with the same per-core performance. So they only make the cores a bit better & slowly add a few cores (mostly to the high end).

high-end phones actually have quite a few cores in the meantime, but there they are staggered for different usage scenarios: a few slow, efficient cores combined with faster and more energy-hungry ones for high-performance tasks. But for most x86 systems that would "waste" to much of the chip I guess.

> but should CPU designs be hobbled simply because the software industry is not where it should be?

Designing CPUs for "the perfect software" is nice, but not what sells to the vast majority of the market. As listed above, there are quite a few niche lines that go in that direction, even if you just look at only Intels offerings.

There's no demand for better performance given current architectures and applications.

It's not hard to imagine more interesting architectures and applications - for example associative language processing, supercomputer-powered robotics, games and UIs that have true cinematic 3D photorealism, or gestural 3D interfaces with very large retina displays.

The problem is really the pace of OS and UI design. We're still using the Xerox Parc GUI model forty years after it was invented, the POSIX OS model some fifty years after it was invented, and the sequential Von Neumann architecture sixty years after it was invented.

These were all breakthroughs at the time, but they should never have become the last word. Research of equivalent creativity seems to have stalled now. IMO it's not just because the low-hanging fruit has been picked, but because there are commercial, academic, and political pressures holding it back.

There may be a game changer generation ten or twenty years from now. But it looks like the pace will be slow until then.

18 cores seems to be the best that Intel does. Which is fairly decent. http://ark.intel.com/products/84683/Intel-Xeon-Processor-E7-...

In laptops, there has been a trend for thinner, lighter and long battery life. So the easiest is to lower power demand. If you increase the number of transistors (by adding more cores), power consumption wouldn't go down enough.

Xeon Phi currently has 61 cores[1] (62 on-die, 1 deactivated for yield reasons), and the next generation coming soon pushes that to 72 cores.

[1] http://www.intel.com/content/www/us/en/processors/xeon/xeon-...

We do have 8, 12 and 18 core CPUs made by Intel. They're just expensive and not made for the typical consumer. My PC at work has the 12 core Xeon. It's nice for compiling large projects, but at home I'm content with a 4 core i7.

http://ark.intel.com/m/products/75283/Intel-Xeon-Processor-E...

http://ark.intel.com/m/products/81061/Intel-Xeon-Processor-E...

Smaller die areas have complications of its own -- heat has less space to travel. It's not as simple as "half the die area, double the cores" -- if you do that, you will end up overheating.

But I think the main issue, as you mentioned, is multi-thread programming. Everyday users spend most of their time in a browser, running Javascript which is mostly synchronous. There are web workers, etc, but the vast majority of sites are still running single threaded JS.

People may want to run multiple simultaneous threads though, which is what additional cores excel at.

No, you may want to run multiple threads, most people want to use their computer. Most people are not limited by their CPU (or even memory these days), the limits are IOPs which an SSD can help with or the speed of their internet connection. Most computers can run 2 or 4 threads at the same time already. Just look at your average Windows computer, even when it's busy, it's probably because 1 core is in use and the program doesn't multithread in a decent manner because it is very hard to program that way.

>No, you may want to run multiple threads, most people want to use their computer.

Whether most people know how their computer works or not, many want to be able to simultaneously: listen to music and/or watch a streaming video, browse multiple web pages, use text editors, specialized business applications, IDE's, and more.

You are going to have a bad time trying to do all of that on a single core, much less a single thread.

I have something useful to say to this but fuck it. I get nothing but down votes here, so why bother investing time in "Hacker" news?

You shouldn't be downvoted like you are, this site is full of assholes apparently. Have an upvote.

I think most people just read what they want to read, regardless of what you actually wrote.

> You are going to have a bad time trying to do all of that on a single core, much less a single thread.

Even desktop CPUs have had the ability to run several threads concurrently on a single core for decades.

And having multiple cores just improves that ability. There's an upper limit to efficiency, but don't tell consumers that while you figure out your quantum processor :-)

Nowhere will you find me arguing that. In fact, this case was already captured in my comment. What you won't find is a single core desktop CPU that has the ability to run several threads concurrently well. The performance will necessarily decrease drastically as you add more concurrent threads.

There is a reason dual core has been standard for awhile. The performance of a single core on a multi-tasking machine is deplorable compared to a machine with additional cores.

Almost any modern desktop you buy (heck even phone) has around 4 cores, it's been this way for years now. After that point the average user doesn't see any particular gain in adding more cores. An 8 core machine really only helps power users. Most users are not running hundreds of threads, look at most your applications, they may have any number of threads running, but only one or two are ever loaded with data. This is the serial world we currently live in.

I'd guess 2 cores is still the majority of machines being sold, though 4 cores is probably a close second by now. 4 cores was certainly not standard on the majority of devices in the last few years.

> Under Erlang/Elixir, we are able to get close to linear speedup from additional cores.

The two main obstacles with parallelization are

1) dividing a problem into a large number of sufficiently parallel tasks, and

2) communication costs.

Erlang isn't a magical bullet that solves these problems. An inherently sequential algorithm doesn't become parallel only because you can cheaply spawn thousands of green threads, and inter-core communication doesn't become faster just by having a convenient message passing mechanism.

Regarding the downvotes: My guess is that you're not being downvoted because of your dissenting opinion, but because you're presenting a misinformed opinion as fact.

You are missing that yes, CPU designs are hobbled by the software industry shortcomings.

Also, you are overlooking that on the traditional architectures memory access becomes slower the more cores you add.

Better integrated GPU and better power consumption on PCs will win on almost all scores until the integrated GPU becomes good enough, and power consumption gets near the theoretical minimum. Then we'll probably see alternative architectures (more alternative than a GPU).

Clearly we should boot the operating system straight onto the GPU.

(Joking, but also a great project if you have an army of graduate students to keep busy)

The PowerVR guys appear to be running a full RTOS w/ memory protection on their GPU FWIW.

I think you found the answer already. Already there are server processors with a lot of cores (i.e. 20) - if you can utilise them all then buy one.

However, for most client workloads, more cores does not translate to better performance because many of those cores will just idle. Single-threaded performance is still the king.

We do see 8 and 16 cores.

Newegg currently lists 10 different 8-core desktop processors and 120 different 8-core server processors. There are also 10-, 12-, 14-, and 16-core processors available to purchase right now.