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I can believe the energy reduction, but how did you compare the quality, and how does it compare to the Q4_0 that I provide? I'd need a compelling reason to replace Q4_0 by Q4_1, and an even more compelling reason to provide both. The idea behind providing Q4_0 was top provide a fast quant for slow computers. I suspect Q4_1 is simply slower but also a bit higher quality. It certainly is a lot bigger with very little quality increase.

In any case, @nicoboss is currently preparing a quite extensive (quality) benchmark over all quant types (including Q4_1). I will reevaluate all quants based on that as well.

@nicoboss while we are at it, another test I'd like to do on all quants is a speed test, to see how different quants work on cpu vs. gpu, possibly both prompt processing and inferencing. I don't thionk I cna put all this on the model page, but I could link to a guidance page, where people could get an idea of relative speeds vs. quality.

While I never performed any performance specific benchmarks as part of the quant quality measurement project so far, I did perform multiple evaluation benchmarks of each model from which I measured the quant quality. Thanks to the files creation and last modified time of the evaluation result I was able to extract the following quant performance measurements. The measurement includes running all the evaluation tests inside the benchmark. All tests were performed with the model being stored fully in RAM without offloading any layers to the GPU but using a GPU to improve prompt evaluation (-ngl 0). Further keep in mind that those are multiple choose benchmarks and so the result is more heavily skewed towards prompt evaluation than token generation than would be the case in most normal use cases.

Comparison between Q4_0 and Q4_1

Conclusion

It seems wrong that Q4_1 performs better than Q4_0. I actually saw the exact opposite. Q4_0 seemed to perform quite a lot better than Q4_1. I monitored the GPU energy consumption during those benchmarks and it was approximately the same no matter the quant so at least in these tests, longer time directly results in more energy consumption for the same task. I do not recommend replacing Q4_0 with Q4_1 from a performance perspective. Keep in mind that I have not considered quality during this comparison.

Future research

I want to come up with some performance tests that are mainly skewed towards token generation instead of prompt evaluation and want to run them CPU only, CPU with offloading computation to GPU (ngl -0), manually offloading layers to GPU, GPU memory RAM overflowing (GGML_CUDA_ENABLE_UNIFIED_MEMORY=1), GPU and using RPC.

Results of all quants

MMLU performance

ARC easy performance:

ARC challenge performance

Winogrande performance

Ah, the claim was that Q4_1 uses less energy than Q4_K_M ("for the quality"), which is a lot of variables. And is, however, is also not backed up by your benchmarks (assuming longer time means more energy usage), unless somehow "for the quality" figures in in favour of Q4_1, which, again seems to be not the case.

@yttria ,it seems Q4_1 is bigger, slower and worse than Q4_K_M, and not that much better than Q4_0, which is even faster.

PS: I didn't try to make you make these benchmarks, but I take them :-) However, they do seem a bit fishy - they follow more or less exactly the quant size, indicating a memory bottleneck, so cpu speed doesn't even figure in. I would assume yttria did it on a cpu with a lot fewer cores, where things can be dramatically different. Which is why I provide Q4_0 in the first place, as a fast quant for cpus. I hope one of the results on all this benchmarking (quality and speed) is to tell us once and for all if Q4_0 actually is useful (it might well be that another quant gives better a better quality/time ratio).

I didn't try to make you make these benchmarks, but I take them :-) However, they do seem a bit fishy - they follow more or less exactly the quant size, indicating a memory bottleneck, so cpu speed doesn't even figure in. I would assume yttria did it on a cpu with a lot fewer cores, where things can be dramatically different. Which is why I provide Q4_0 in the first place, as a fast quant for cpus. I hope one of the results on all this benchmarking (quality and speed) is to tell us once and for all if Q4_0 actually is useful (it might well be that another quant gives better a better quality/time ratio).

Great point. I'm aware that the shared performance test results are not perfect which is not surprising as I never indended thouse tests to be used to measure quant performance . I did all tests on a Threadripper PRO 7975WX (32 core 64 threads) while also using the GPU to do compuatations. This resulted in super fast prompt evaluation during prompt evaluation heavy tests. So thouse tests are indeed almost certainly memory bottlenecked which might not always be the case during normal use depending on the hardware. I'm wondering if there are really any realistic cases where LLMs are not memory bottlenecked. After just a few threads I start seeing deminishing returns when adding more. Usual consumer hardware has just dual channel memory and so should be bottelnacked even faster. I definately want to do more carefull testing regarding this and maybe even test on more mainstream hardware like my laptop. I actually already did many GGUF performance tests one year ago during the planing stage of my StormPeak build. I did so by changing the memory channels and memory clock-speed and amount of threads assigned to llama.cpp. The conclusion back then was pritty much the more memory channels and the faster memory I get the better the performance of GGUF files executed on the CPU will be. This was the main reason I decided to go for the much more expensive Threadripper PRO with octa-channel instead of the normal Threadripper lineup with quad-channel memory for my StormPeak node.

I agree with your methodology, these side effects were of course not the goal. There are lots of realistic cases where the cpu is the bottleneck, though. In fact, most cpus will be the bottleneck when confronted with IQ quants, and memory bottlenecked with normal Q quants. Which is totally in line with your experience (no IQ quants last year). There are even lots of systems where Q4_K_M might be a bottleneck, which is why I added Q4_0 quants back - purely for speed.

Whenever I get to my performance benchmarks, my plan is to make a 4-core baseline test for specifically slower cpus. There are a lot of people who run smaller models on not very beefy laptops, for example.

This is my test on M3 Max processing and generating a fixed number of tokens:

Prompt processing

Token generation

well, the Q4_0 seems to more energy-efficient than Q4_1, and is probably higher quality per bit, too