vulkan: remove the need for the dryrun

[jeffbolznv]

Allocate pipelines and descriptor sets when requested.

Reallocate the prealloc buffers when needed, and flush any pending work before reallocating.

For rms_partials and total_mul_mat_bytes, use the sizes computed the last time the graph was executed.

The dryrun is a small but consistent overhead where the GPU is idle. I get an average of maybe 1-2% improvement with it removed, though my numbers have been noisy lately.

I didn't totally rip out all the logic yet, I wanted to keep the diffs smaller to make it more clear how the new code works.

before:

Z:\github\jeffbolznv\llama.cpp\build\bin\RelWithDebInfo>llama-bench.exe -fa 1 -n 128 -p 0 -r 10 --prio 1 -m c:\models\DeepSeek-R1-Distill-Llama-8B-Q4_K_M.gguf -m c:\models\DeepSeek-R1-Distill-Llama-8B-Q6_K.gguf -m c:\models\DeepSeek-R1-Distill-Qwen-14B-Q4_K_M.gguf -m c:\models\Llama-3.2-1B.Q2_K.gguf -m c:\models\Llama-3.2-1B.Q3_K_S.gguf -m c:\models\llama-3.2-3b-instruct-q5_k_m.gguf -m c:\models\Qwen_Qwen3-30B-A3B-Q2_K.gguf -m c:\models\Qwen2.5-7B-Instruct-1M-Q2_K.gguf  -m c:\models\\deepseek-v2-lite-safetensors\deepseek-v2-lite-Q4_K_M.gguf -m c:\models\gpt-oss-20b-mxfp4.gguf -m c:\models\Phi-3-mini-4k-instruct-q4.gguf -m c:\models\llama-2-7b.Q4_0.gguf -m c:\models\llama-3.2-3b-instruct-q8_0.gguf -m c:\models\Mistral-22B-v0.2-Q4_K_M.gguf -m c:\models\nvidia_Llama-3_3-Nemotron-Super-49B-v1_5-Q4_K_S.gguf
ggml_vulkan: Found 1 Vulkan devices:
ggml_vulkan: 0 = NVIDIA GeForce RTX 5090 (NVIDIA) | uma: 0 | fp16: 1 | bf16: 1 | warp size: 32 | shared memory: 49152 | int dot: 1 | matrix cores: NV_coopmat2
| model                          |       size |     params | backend    | ngl | fa |            test |                  t/s |
| ------------------------------ | ---------: | ---------: | ---------- | --: | -: | --------------: | -------------------: |
| llama 8B Q4_K - Medium         |   4.58 GiB |     8.03 B | Vulkan     |  99 |  1 |           tg128 |        237.16 ± 3.72 |
| llama 8B Q6_K                  |   6.14 GiB |     8.03 B | Vulkan     |  99 |  1 |           tg128 |        196.74 ± 6.25 |
| qwen2 14B Q4_K - Medium        |   8.37 GiB |    14.77 B | Vulkan     |  99 |  1 |           tg128 |        128.58 ± 3.47 |
| llama 1B Q2_K - Medium         | 546.50 MiB |     1.24 B | Vulkan     |  99 |  1 |           tg128 |       828.66 ± 20.21 |
| llama 1B Q3_K - Small          | 604.50 MiB |     1.24 B | Vulkan     |  99 |  1 |           tg128 |        826.18 ± 8.65 |
| llama 3B Q5_K - Medium         |   2.16 GiB |     3.21 B | Vulkan     |  99 |  1 |           tg128 |       380.99 ± 23.22 |
| qwen3moe 30B.A3B Q2_K - Medium |  10.15 GiB |    30.53 B | Vulkan     |  99 |  1 |           tg128 |       263.97 ± 13.83 |
| qwen2 7B Q2_K - Medium         |   2.80 GiB |     7.62 B | Vulkan     |  99 |  1 |           tg128 |       240.75 ± 14.32 |
| deepseek2 16B Q4_K - Medium    |   9.65 GiB |    15.71 B | Vulkan     |  99 |  1 |           tg128 |       292.99 ± 37.92 |
| gpt-oss 20B MXFP4 MoE          |  11.27 GiB |    20.91 B | Vulkan     |  99 |  1 |           tg128 |       275.93 ± 20.96 |
| phi3 3B Q4_K - Medium          |   2.23 GiB |     3.82 B | Vulkan     |  99 |  1 |           tg128 |       357.16 ± 16.19 |
| llama 7B Q4_0                  |   3.56 GiB |     6.74 B | Vulkan     |  99 |  1 |           tg128 |       264.03 ± 10.48 |
| llama 3B Q8_0                  |   3.18 GiB |     3.21 B | Vulkan     |  99 |  1 |           tg128 |       312.49 ± 20.09 |
| llama ?B Q4_K - Medium         |  12.42 GiB |    22.24 B | Vulkan     |  99 |  1 |           tg128 |         92.71 ± 0.30 |
| deci 70B Q4_K - Small          |  26.66 GiB |    49.87 B | Vulkan     |  99 |  1 |           tg128 |         50.06 ± 0.16 |

after:

Z:\github\jeffbolznv\llama.cpp\build\bin\RelWithDebInfo>llama-bench.exe -fa 1 -n 128 -p 0 -r 10 --prio 1 -m c:\models\DeepSeek-R1-Distill-Llama-8B-Q4_K_M.gguf -m c:\models\DeepSeek-R1-Distill-Llama-8B-Q6_K.gguf -m c:\models\DeepSeek-R1-Distill-Qwen-14B-Q4_K_M.gguf -m c:\models\Llama-3.2-1B.Q2_K.gguf -m c:\models\Llama-3.2-1B.Q3_K_S.gguf -m c:\models\llama-3.2-3b-instruct-q5_k_m.gguf -m c:\models\Qwen_Qwen3-30B-A3B-Q2_K.gguf -m c:\models\Qwen2.5-7B-Instruct-1M-Q2_K.gguf  -m c:\models\\deepseek-v2-lite-safetensors\deepseek-v2-lite-Q4_K_M.gguf -m c:\models\gpt-oss-20b-mxfp4.gguf -m c:\models\Phi-3-mini-4k-instruct-q4.gguf -m c:\models\llama-2-7b.Q4_0.gguf -m c:\models\llama-3.2-3b-instruct-q8_0.gguf -m c:\models\Mistral-22B-v0.2-Q4_K_M.gguf -m c:\models\nvidia_Llama-3_3-Nemotron-Super-49B-v1_5-Q4_K_S.gguf
ggml_vulkan: Found 1 Vulkan devices:
ggml_vulkan: 0 = NVIDIA GeForce RTX 5090 (NVIDIA) | uma: 0 | fp16: 1 | bf16: 1 | warp size: 32 | shared memory: 49152 | int dot: 1 | matrix cores: NV_coopmat2
| model                          |       size |     params | backend    | ngl | fa |            test |                  t/s |
| ------------------------------ | ---------: | ---------: | ---------- | --: | -: | --------------: | -------------------: |
| llama 8B Q4_K - Medium         |   4.58 GiB |     8.03 B | Vulkan     |  99 |  1 |           tg128 |        239.51 ± 7.95 |
| llama 8B Q6_K                  |   6.14 GiB |     8.03 B | Vulkan     |  99 |  1 |           tg128 |        197.76 ± 8.86 |
| qwen2 14B Q4_K - Medium        |   8.37 GiB |    14.77 B | Vulkan     |  99 |  1 |           tg128 |        128.50 ± 4.10 |
| llama 1B Q2_K - Medium         | 546.50 MiB |     1.24 B | Vulkan     |  99 |  1 |           tg128 |       824.48 ± 11.02 |
| llama 1B Q3_K - Small          | 604.50 MiB |     1.24 B | Vulkan     |  99 |  1 |           tg128 |      635.92 ± 253.03 |
| llama 3B Q5_K - Medium         |   2.16 GiB |     3.21 B | Vulkan     |  99 |  1 |           tg128 |       384.39 ± 23.94 |
| qwen3moe 30B.A3B Q2_K - Medium |  10.15 GiB |    30.53 B | Vulkan     |  99 |  1 |           tg128 |       260.74 ± 22.91 |
| qwen2 7B Q2_K - Medium         |   2.80 GiB |     7.62 B | Vulkan     |  99 |  1 |           tg128 |       240.84 ± 14.85 |
| deepseek2 16B Q4_K - Medium    |   9.65 GiB |    15.71 B | Vulkan     |  99 |  1 |           tg128 |       301.72 ± 31.62 |
| gpt-oss 20B MXFP4 MoE          |  11.27 GiB |    20.91 B | Vulkan     |  99 |  1 |           tg128 |       282.66 ± 21.94 |
| phi3 3B Q4_K - Medium          |   2.23 GiB |     3.82 B | Vulkan     |  99 |  1 |           tg128 |       368.81 ± 12.07 |
| llama 7B Q4_0                  |   3.56 GiB |     6.74 B | Vulkan     |  99 |  1 |           tg128 |        270.71 ± 3.88 |
| llama 3B Q8_0                  |   3.18 GiB |     3.21 B | Vulkan     |  99 |  1 |           tg128 |        319.78 ± 3.61 |
| llama ?B Q4_K - Medium         |  12.42 GiB |    22.24 B | Vulkan     |  99 |  1 |           tg128 |         92.07 ± 1.51 |
| deci 70B Q4_K - Small          |  26.66 GiB |    49.87 B | Vulkan     |  99 |  1 |           tg128 |         49.97 ± 0.16 |

[0cc4m]

I do have the optimal setup to test this, with a slow server CPU + 3090:

model	size	params	ngl	fa	test	t/s (before)	t/s (after)	diff
llama 8B Q2_K - Medium	2.95 GiB	8.03 B	99	1	tg128	117.20 ± 0.31	119.50 ± 0.24	+2.0%
llama 8B Q4_K - Small	4.36 GiB	8.03 B	99	1	tg128	122.78 ± 8.91	129.57 ± 0.41	+5.5%
llama 8B Q4_0	4.33 GiB	8.03 B	99	1	tg128	142.21 ± 13.40	151.45 ± 0.45	+6.5%
llama 8B Q4_1	4.77 GiB	8.03 B	99	1	tg128	139.90 ± 0.39	142.20 ± 0.24	+1.6%
llama 8B Q8_0	7.95 GiB	8.03 B	99	1	tg128	93.47 ± 0.31	94.05 ± 2.76	+0.6%
qwen3moe 30B.A3B Q2_K - Medium	10.48 GiB	30.53 B	99	1	tg128	156.66 ± 13.84	159.81 ± 17.27	+2.0%
gpt-oss 20B Q8_0	11.27 GiB	20.91 B	99	1	tg128	156.70 ± 14.05	154.48 ± 22.33	-1.4%

The test good, but it's gonna take me a little while to go through the code.

[0cc4m]

Can you fix the conflict?

[jeffbolznv]

Rebased.

[0cc4m]

Okay, I get what this is doing and results are positive, in my tests. What's your plan now? Clean up the unused code before merge?

[jeffbolznv]

Sure, I can do that tomorrow.