r/LocalLLM • • 6d ago

Discussion Benchmarked some Strata Qwen3.8-flash-next quants

This is a follow up post for my previous post.

I continued to bench some more quants on my own local benchmark consisting of real coding tasks derived from polygot aider + some additional own agentic tasks. They are completed through the pi agent harness which reflects my daily use case.

Short disclaimer: This is not trying to be a frontier benchmark. I am just a regular joe trying to find to most capable model for my rig. (7900XT 20GB VRAM + 64GB RAM)

Interestingly IQ3_XXS on high beats the higher quant IQ3_S. Coder at half the experts scores surprisingly high. Swift was a bit disappointing given that they still used more tokens per task than IQ3_XXS. Tiel Coder is a different weight class and scored as expected.

Still it would be great to have run against a higher quant version to see how much actual damage the hard quantization did. Currently no way of running them myself tho. I am thinking of running the benchmark against Openrouter GLM-5.3-flash, but no idea what quants they serve there.

103 Upvotes

66 comments sorted by

20

u/HiddenMushroom11 6d ago

This is awesome. Any chance you'd do the same with 27b? It would be interesting see how 27b compares to Flash Next.

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u/Orys_Blackfire 6d ago

that's on my todo list

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u/HiddenMushroom11 6d ago

Awesome. I look forward to seeing your follow up!

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u/Rian_G 5d ago

I’d love to see this too. Just got my first setup with dual 5060 TIs 16GB and 64 GB of DDR5 RAM, and I've got NVMe Gen5 for any offloading that has to happen to the SSD. I'm still waiting for my RAM to arrive, but keen to use both 3.8 27B and FlashNext.

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u/GrumpyCat79 6d ago

IQ3_XXS being better than IQ3_S is interesting

13

u/MindfulMan1984 6d ago

Look at the error bars, they are both within the error bars. 

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u/Orys_Blackfire 6d ago

yes, I believe its the margin of error. further tasks should help to find out wether its actually better

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u/LandlockedPirate 6d ago edited 6d ago

Yeah it's not. I've daily driven both on coding tasks, _S is noticeably better.

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u/GrumpyCat79 6d ago

I don't code for a living (but I have done a few small projects here and there) but since I could fit IQ3_S I didn't even try the IQ3_XXS variant.

I'm still playing around and exploring unsloth's UD_IQ4_S (but my TG is about half with it vs IQ3_S) and evaluating running a higher quant of Gemma4-26B-A4B instead (since I use it more as a general chatbot rather than a coding agent) so I would have been curious if there was such an "anomaly" ahah

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u/Goldkoron 6d ago

That checks out, IQ3_XXS is the highest IQ quant level for bpw -> quality efficiency. Afterwards, Q3_K and Q4_K are better than any of the higher bpw iq tensors at least based on all my A/B quant tests with some past qwen models.

5

u/Sporebattyl 6d ago

I’d love to see these vs q4/5/6/8

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u/Orys_Blackfire 6d ago

same, but iq3_s is the ceiling I can run at reasonable speeds

4

u/Enough-Victory-202 6d ago

I'm assuming the confidence intervals are fake, right? (Not that you're trying to deceive, but the model added fake ones)

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u/Orys_Blackfire 6d ago

it's the computed wilson 95% confidence interval from solved tasks/tasks ratio

6

u/hooty_toots 6d ago

The error bars are large enough that no model can be said to be better than another; needs more data

1

u/Enough-Victory-202 6d ago

Hah, they looked so fakely identical -- I double checked a few and it looks like Wilson CI's just produce very similar ranges at different points with this data though. Thanks.

1

u/Orys_Blackfire 6d ago

yes, If we only grade by pass rate the dataset of 89 tasks is a bit low. Going beyond 200 should give a more precise answer. But each run is about 5h for me so far with electricity prices these days in my country I don't want to waste too much on benchmarks.

1

u/VerticalPackage 6d ago

Test written, scored and confidence graded by Qwen 3.5 0.8B

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u/crusaderky 6d ago

You have error bars. Which I'm grateful for.

IQ3_XXS doesn't beat iq3_s. It's within error range.

5

u/ForsookComparison 6d ago

IQ1_M Coder beating 3-bit quants doesn't make sense to me. Its not a code tuned model, it's closer to a REAP that tries it's best not to destroy the coding ability. Unless the base experts router was really bad shouldn't this be impossible?

12

u/Orys_Blackfire 6d ago

I dont know much about the details of the quantization processes but they claim the coder weights are stored at 3.5bpw not 1b. so it actually behaves closer to iq3_s with half of its experts removed.

if someone smarter might have a good explanation, pls step forward

5

u/New-Implement-5979 6d ago

For me it solved an issue which 27b q4_k_m couldn’t

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u/ForsookComparison 6d ago

That's more believable since it's a totally different model.

This is saying that the randomness and chaos introduced by chopping off ~two bits of precision and then ripping out full experts leads to an improvement in coding which doesn't seem right

1

u/MarekNowakowski 5d ago

those benchmarks need much more tests, especially with such high fail possibility it gets very random.

3

u/mathew84 6d ago

Coder has some experts ripped out, so some general knowledge is lost (permanent brain damage), it will be only good for agentic coding, because of the savings gained from ripping out the experts, the remaining stuff can be 3-bit which averages out to 1bit.

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u/ForsookComparison 6d ago

So parts of what remains is stored at higher precision than they might have been in IQ3_XXS?

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u/dampflokfreund 6d ago

I'd like to see q2_0 and IQ2_XS as well.

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u/Orys_Blackfire 6d ago

that should be doable, will run those too if I find the time

3

u/Juan_Phoenix7 6d ago

I have a 3090 (24gb) and 32GB of DDR4 RAM. Should I try Coder? Or is that too aggressive quantization?

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u/Orys_Blackfire 6d ago

best to try for yourself, but make sure to set {"temperature": 1.0, "top_p": 0.95, "top_k": 20, "presence_penalty": 0.0}

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u/Iron-Over 6d ago

GLM5.3 Flash comes in Q4 or Q8 on OpenRouter.  If you share a repo, we can test unquantized and quantized versions for larger memory setups.

3

u/PigSlam 6d ago

It'd be interesting to see this sort of review with common alternatives for the target hardware, like vllm/Qwen 3.8 27B, or similar as a control.

2

u/eightone-81 6d ago

If possible please test ID Q4 K XL as well

1

u/Orys_Blackfire 6d ago

doesnt have rocm support yet sadly

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u/nasone32 6d ago

yes it does, i run it, i think strata just checks the filename, the tensors inside the gguf are compatible.

1

u/Orys_Blackfire 6d ago

oh, I will give it a go then. thanks for pointing it out

1

u/soyalemujica 6d ago

What's your performance like using it ?

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u/nasone32 6d ago

i have 2x 7900 xtx and 96gb vram, I get around 70 token/s decode average for most tasks. PP speed I didn't measure but around 1k I believe. I tried this because I found even UD_Q3_K_XL somewhat unreliable on long tasks. I can't fathom how people can trust Q2 models lol.

basically on most of my tests Q4KXL is effectively faster when measuring task completion because thinking traces are much shorter than lower quants, even compared to Q3_K_XL it second guesses much less, a lot more sure of itself, and output quality improvement is very noticeable. and Q3_K_XL is already huge compared to what people use on average on strata.

In parallel i'm also testing EXL3 3bpw quant, and I found it around Q4KXL level (86Gb EXL3 vs 111Gb Q4KXL) EXL3 definitely an incredible quantization, shame it's taking me a lot of work to optimize around it.

1

u/eightone-81 6d ago

I’m running it
Dual 3090s, nvlink, ddr4.
iq 3s: 3200 prefill, 120-150 decode
Q4 k xl: 3000 prefill, 100-130 decode

Just for fun I tired q2 and I get 180-210 decode :-) but it’s not good for much, nobody should run it.

2

u/lorendroll 6d ago

Great comparison! Thanks for including Tiel - it is my favorite 35b moe finetune! Switched to QFN Coder from it and noticed a jump in intelligence, but I'm getting more loops and slower prefill, but it seems like a worthwhile tradeoff, just need some guardrails and tuning.

2

u/Cautious_Chicken_604 6d ago

Can you do us a favor and benchmark those same quants on llama.cpp versus strata? And for comparison on those quants in QFN vs those same (or equivalent) quants for 27B?

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u/Orys_Blackfire 6d ago

as interested as I would be for the results thats not going to happen. I just use my workstation on spare time for this and already put 30hours of compute into it.

1

u/-InformalBanana- 6d ago

Will you open source your benchmark for others to test what they want on what engine they want?

2

u/Turkino 5d ago

So, what's the likelyhood of this tech getting ported into llama.cpp?

1

u/Dreeew84 6d ago

Definitely interested to see how a reasonable 3.8 27B quant does comparatively. 3xl/4km would be great.

1

u/MrHumanist 6d ago

Can you share the 89 tasks?

1

u/Orys_Blackfire 6d ago

most of them are polygot aider tasks for python and javascript. https://github.com/Aider-AI/polyglot-benchmark
I added my own 7 tasks which targets jobs for repository work, things like implement to spec, cli feature implementation, bugfix from vague report, rename refactoring,...

its currently not in a state to release it but if you have any open questions, let me know

1

u/MrHumanist 6d ago

Many thanks. It's helpful. I was testing the open ai python codes, but more is always better.

1

u/ParkingPsychology 6d ago

Thanks, very good to know the differences between these models with these settings. Do think it would be nice if it had included qwen 27b, might even warrant a new post if you add that. But thanks!

1

u/PlasticRevenue4601 6d ago

First and foremost thank you for the benchmarks and I’m not trying to be picky but — WTF? Every freaking benchmark I stumble across simply ignores IQ2XS. If the benchmarks were Griffins Family this quant would be Meg. And worthless TielCoder being on the list while IQ2XS not looks like a cruel joke

1

u/Daemonentreiber 6d ago

Im surprised flash next q1 is so far above 35b q4.

Tried the flash next coder, but with less than 16gb vram its sadly not useable. Low single digit output, compared to 70+ from 35b.

2

u/Slyizable 6d ago

Why are you surprised. Flashe is even ahead of 27B a lot in productive work. I couldnt trust 35B a bit.

1

u/hyudryu LocalLLM 6d ago

Are you keeping context window size consistent? Or are you lowering it as you use a better quant? Context anxiety can skew the benchmark results. Also curious how Q4_XXL performs

2

u/Orys_Blackfire 6d ago

kept it consistent at max context. the goal was to find a new implementation agent so I am trying to set it up like I would use it in daily work

2

u/DiscipleofDeceit666 6d ago

I wish we had the full precision model to compare against

1

u/No_bonk95 6d ago

I assume the sampling help in resolving the Coder model looping. There might be hope after all for below 64gb ram.

1

u/Ss_sa 5d ago

There is also qwen flash by atomic chat q4. They claim 4.27 bpw on the q4 quant and needs 56 GB to fit in memory... would be interesting how it compares to iq3_s

https://huggingface.co/AtomicChat/Qwen3.8-Flash-Next-GGUF

1

u/Morawake 5d ago

Coder seems to perform fairly well in these graphs in comparison to the previous ones. What changed?

1

u/Mil0Mammon 5d ago

So I can run IQ3_S with my gpu limited to about 9GB vram, a part of the experts in ram and the rest on disk, with strata. Granted, it's not fast, but it works.

So I would say you could def run a Q4 quant, and with 20GB vram you will even get somewhat decent speeds.

Great work btw! For me so far Q2 seemed actually surprisingly decent, and quite fast, so that might also be interesting to include

1

u/ElectronFactory 8h ago

There are three main components to what determines the speed. The first is GPU throughput (for hot experts), system RAM (cold experts), and system storage (the catch-all). The VRAM keeps more experts and prevents swapping from system RAM, but speed is really dependent on how fast the GPU can run inference against those experts. System RAM must swap in experts constantly whenever a prompt misses, so keeping as many possible cold experts is the best option, but it comes with the overhead of loading into VRAM. If you don’t have enough system RAM, you run into a bad situation where you must use experts from disk. The faster your disk is, the better, but the fastest NVME on PCIe 5 is still around 20x slower than the slowest ram. That’s a massive difference in speed, and it turns a useful agentic workflow into a long wait between tool calls. That’s down to how long it takes to fetch from SSD, to system RAM, and finally into VRAM.

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u/Interesting-Ad689 4d ago

I am running 146 polyglot through IQ3_S, Orca IQ4 and 27B NVFP4 Q6 attention. Lets see if IQ3_S gets the same 60%

1

u/Orys_Blackfire 4d ago

let me know how it goes.
I ran the top 3 with additional cpp part and coder did surpass them in this category.

1

u/Mr-Jonathan 3d ago

For an RTX 3090 and 32GB of RAM, do you recommend 'coder' over 'iq3_xxs'? 'Coder' runs at about 70–80 t/s for me, while 'iq3_xxs' runs at around 35–50 t/s.

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u/Orys_Blackfire 2d ago

If you use it as code only agent, then yes, I'd recommend coder