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Comment by quantumwoke | Hacker News Reader

I've weighed up the pros and cons, and my next processor will be the 32 core AMD cpu. This seems much better value than anything Intel has to offer.

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The last gen 1900x (3.8 GHz 8 core) is on sale now for only $300

AMD becoming competitive again is one of the better things to happen in tech in recent years

The 2700 is available for $225 on Amazon.

Yeah, depends if you want 2 memory channels or 4 memory channels.

Ah, forgot the 1900x was Threadripper.

I got a Ryzen 7 for my recent build and am pretty happy with it.

Same, bought a 2700x and couldn't be happier... the extra cores does wonders for using something like intellij whilst browsing / gaming. You only need something like an 8700k / 8086k if you have a 100hz+ monitor and want to spend more money than necessary on a dead socket. AMD are really landing the uppercuts this time round

I've got a R5 1600X with overclocked RAM (3GHz) and a 144Hz display. I've yet to encounter a game that doesn't bottleneck on the GPU with vsync on. Either it hits beyond 144fps and it wouldn't matter, or its below 144fps bottlenecked on the GPU.

Im in the same boat, my current processor I got was an intel specifically for the high single thread speed (a few performance heavy single thread games), but honestly the bit of extra clock speed hasn't really done it for me. The improvement is marginal compared to the ability to scale across cores and I expect pretty much everything I use now to take advantage of it. These days I have so many more programs concurrently open/in operation compared to the past, many of which are now fully capable of each using multiple cores, and I can still see myself using more. While my system isn't a spring chicken anymore I still have run into full system utilization a lot sooner and more often than I ever expected when I built this.

the 16 physical core TR is glorious so I'm sure you'll enjoy the 32 core even more!

I'm going to wait 1-2 years to upgrade since I just got the 1st gen.

Much agreed. I've wanted a high core count cpu for absolutely no reason for the longest time. I can't wait to spend thousands of dollars on a cpu just to improve compile times by a few seconds. -j64 anyone?

It's a beast! I'm not sure if I'd give up single-thread speed, but if you can load those cores, it's an incredible offer.

I'd love to see more popular processors with high core count, even if at the cost of single thread performance. When even a phone CPU has 8 cores, being able to use the parallelism on the stuff we normally don't use it would improve life for everyone.

And, with high core counts, we can start playing with things like dedicating cores (and their L1 caches) to single tasks, kind of specializing them as we do with mainframes.

as core count goes up the number of tasks that can be sped up starts to shrink, because memory access and throughput become more and more of a limiter. That is why you tend to see huge l3 caches on the big core cpus, it helps but it can still be a challenge to load up all 32 cores and get any speedup, for many workloads. l3 cache is not THAT much faster than ram.

that is why I tend to eye the ~6 core machines for desktop use, higher single core mhz on them

If we can balance the L1 cache eviction rate for the extra cores (since L1 is not shared), memory bandwidth pressure will be lower. These monsters also have a lot of memory channels to address memory hunger.

I still think we can push the envelope a bit further for most common desktop software.

There is definitely room to improve how often and efficiently desktop software utilizes more cores, but I don't expect it will be common that ~32 cores gets you much gain over ~8. But when you do have a workload that can benefit, like if you know GCC will compile a huge c++ project linearly faster up to 32 cores, then it is VERY welcome!

If you have cores to spare, you can do incremental compilation every time you save a file. You can also do a lot of speculative work that may be thrown away but, in case it's needed, it's already done.

There is no such thing as too many cores ;-)

L1 cannot be too big and it should not grow any larger. L2 is a better option being 'only' 3 times slower than L1 (L1 tend to be ~3 clocks to read). L3 is an interesting concept. Communication through L3 is quite beneficial in concurrent programming when done right; other than that it's there to hide the latency of accessing RAM. However, it's shared and easy to trash.

The software developers could do a lot for memory throughput hungry applications (datastructure layout, not using bloated strings for everything, not using linked lists, etc.), alas memory based optimizations almost never happen and tend to require a great deal of hardware understanding + non scripting language(s).

> L1 cannot be too big and it should not grow any larger. L2 is a better option

L1 and L2 grow linearly with the number of cores. If you have cores to burn, pinning processes makes a lot of sense.

rbanffy, it was meant per core. Counting L1/L2 across the entire die is rather pointless.

Pinning makes most sense in NUMA indeed. Nowadays my impression is that often times the multicore/socket hardware tend to be chopped down by virtual machines, though.

If you use VMs and don't pin VMs to cores (which is pretty sensible) yes, but if you run your processes on your metal, pinning processes will reduce pressure on their L1/L2 caches if a given process is running on it constantly, the odds the caches have the "right" data increase. The same goes for the processes that are not pinned, as they don't need to compete with the pinned one (unless they have the misfortune of being scheduled on those cores). In the end, it'll look like your cache is bigger.

It depends on your workload. If you are using all these cores (ex: compiling) then that's probably the best option.

If you are gaming however, 32 core is mostly useless and you should probably go with single thread performance. Intel i5 are still the CPUs of choice for gamers, though AMD Ryzen 5 are not bad either.

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