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Mirrored from ggml-org/llama.cpp#17505

This PR makes the following changes to the CUDA FlashAttention code:

  • All kernels have been extended with support for attention masks that are not padded in mask->ne[1] direction. This is done by applying a modulo on the mask column that is being read so no conditional statements need to be evaluated. The impact on performance is negligible and I do not deem it necessary to compile additional template specializations. See ggml : remove KQ mask padding ggml-org/llama.cpp#16309 . cc @ggerganov .
  • The mma kernel has been extended with support for Volta tensor cores. Previously the WMMA kernel was used. The WMMA kernel is now only needed for AMD. After AMD support has been added to the mma kernel the WMMA kernel can be safely removed, leaving only 3 kernels to maintain going forward. On master the mma kernel has defects w.r.t. tile shapes that do not manifest as bugs, those should be fixed with this PR and I think it is now feasible for other developers to add support for e.g. AMD wmma instructions. cc @zhang-hui-yulo @jiachengjason @unverbraucht .
  • The tile template in mma.cuh has been extended with additional, optional arguments to safely handle situations where tiles of the same shape can have different physical data layouts.
  • The mma kernel is refactored to allow more flexible configuration. The configuration is now also done without the use of templating which seems to be causing issues for __launch_bounds__ when using ROCm (as of right now ROCm is not used).
  • The mma kernel is extended with support for out-of-bounds checks in direction of K->ne[1]. As with the tile kernel, because this comes at a cost to performance it is still preferable to pad the KV cache length. As of right now this is still required to be 256, for the currently supported GPUs it should be possible to lower this to 128 without issue once the WMMA kernel has been completely replaced. For Hopper it may still make sense to have a padding of 256 but as it is I have no idea whether the 256x64 instruction would actually have better performance than the 128x64 instruction.

As of right now the interface in mma.cuh is suboptimal and long-term I intend to refactor it to allow the use of tensor cores in a more uniform way. However, I don't know the exact requirements until we have proper support for AMD WMMA and AMD MFMA instructions. So for now I think the correct choice is to prioritize getting working support for those at the cost of maintainability and to do a refactor afterwards.

V100 performance
GPU Model Microbatch size Test t/s master t/s 277014f50 Speedup
V100-PCIE-32GB deepseek2 16B Q4_0 1 pp512@d32768 84.06 89.23 1.06
V100-PCIE-32GB deepseek2 16B Q4_0 2 pp512@d32768 88.28 86.50 0.98
V100-PCIE-32GB deepseek2 16B Q4_0 4 pp512@d32768 122.04 134.50 1.10
V100-PCIE-32GB deepseek2 16B Q4_0 8 pp512@d32768 159.61 204.43 1.28
V100-PCIE-32GB deepseek2 16B Q4_0 16 pp512@d32768 187.50 274.82 1.47
V100-PCIE-32GB deepseek2 16B Q4_0 32 pp512@d32768 208.08 340.50 1.64
V100-PCIE-32GB deepseek2 16B Q4_0 64 pp512@d32768 196.49 312.07 1.59
V100-PCIE-32GB deepseek2 16B Q4_0 128 pp512@d32768 217.64 371.18 1.71
V100-PCIE-32GB deepseek2 16B Q4_0 256 pp512@d32768 227.55 408.51 1.80
V100-PCIE-32GB deepseek2 16B Q4_0 512 pp512@d32768 250.76 432.14 1.72
V100-PCIE-32GB gemma 2B Q4_0 1 pp512@d32768 196.73 276.43 1.41
V100-PCIE-32GB gemma 2B Q4_0 2 pp512@d32768 341.32 472.67 1.38
V100-PCIE-32GB gemma 2B Q4_0 4 pp512@d32768 233.69 461.42 1.97
V100-PCIE-32GB gemma 2B Q4_0 8 pp512@d32768 433.09 705.18 1.63
V100-PCIE-32GB gemma 2B Q4_0 16 pp512@d32768 779.04 1095.12 1.41
V100-PCIE-32GB gemma 2B Q4_0 32 pp512@d32768 981.00 1506.68 1.54
V100-PCIE-32GB gemma 2B Q4_0 64 pp512@d32768 859.59 1260.66 1.47
V100-PCIE-32GB gemma 2B Q4_0 128 pp512@d32768 1032.55 1735.64 1.68
V100-PCIE-32GB gemma 2B Q4_0 256 pp512@d32768 1089.22 1833.70 1.68
V100-PCIE-32GB gemma 2B Q4_0 512 pp512@d32768 995.95 1613.81 1.62
V100-PCIE-32GB llama 1B Q4_0 1 pp512@d32768 237.92 323.72 1.36
V100-PCIE-32GB llama 1B Q4_0 2 pp512@d32768 417.22 588.65 1.41
V100-PCIE-32GB llama 1B Q4_0 4 pp512@d32768 448.34 838.65 1.87
V100-PCIE-32GB llama 1B Q4_0 8 pp512@d32768 824.46 1445.37 1.75
V100-PCIE-32GB llama 1B Q4_0 16 pp512@d32768 1435.92 1917.20 1.34
V100-PCIE-32GB llama 1B Q4_0 32 pp512@d32768 1769.39 2566.43 1.45
V100-PCIE-32GB llama 1B Q4_0 64 pp512@d32768 1991.61 2289.92 1.15
V100-PCIE-32GB llama 1B Q4_0 128 pp512@d32768 2391.19 2843.04 1.19
V100-PCIE-32GB llama 1B Q4_0 256 pp512@d32768 2312.60 2559.85 1.11
V100-PCIE-32GB llama 1B Q4_0 512 pp512@d32768 1900.53 2137.76 1.12
V100-PCIE-32GB llama 8B Q4_0 1 pp512@d32768 61.12 81.47 1.33
V100-PCIE-32GB llama 8B Q4_0 2 pp512@d32768 115.57 154.44 1.34
V100-PCIE-32GB llama 8B Q4_0 4 pp512@d32768 120.26 220.87 1.84
V100-PCIE-32GB llama 8B Q4_0 8 pp512@d32768 215.88 323.48 1.50
V100-PCIE-32GB llama 8B Q4_0 16 pp512@d32768 380.43 467.35 1.23
V100-PCIE-32GB llama 8B Q4_0 32 pp512@d32768 470.78 656.82 1.40
V100-PCIE-32GB llama 8B Q4_0 64 pp512@d32768 228.56 456.01 2.00
V100-PCIE-32GB llama 8B Q4_0 128 pp512@d32768 278.85 670.43 2.40
V100-PCIE-32GB llama 8B Q4_0 256 pp512@d32768 307.17 872.91 2.84
V100-PCIE-32GB llama 8B Q4_0 512 pp512@d32768 314.34 932.41 2.97
Other GPU performance
GPU Model Microbatch size Test t/s master t/s e44ebb095 Speedup
MI60 / MI50 llama 8B Q4_0 1 pp512@d32768 59.80 64.40 1.08
MI60 / MI50 llama 8B Q4_0 2 pp512@d32768 106.46 113.46 1.07
MI60 / MI50 llama 8B Q4_0 4 pp512@d32768 119.84 97.07 0.81
MI60 / MI50 llama 8B Q4_0 8 pp512@d32768 162.89 167.55 1.03
MI60 / MI50 llama 8B Q4_0 16 pp512@d32768 228.46 229.93 1.01
MI60 / MI50 llama 8B Q4_0 32 pp512@d32768 269.06 268.69 1.00
MI60 / MI50 llama 8B Q4_0 64 pp512@d32768 291.15 289.38 0.99
MI60 / MI50 llama 8B Q4_0 128 pp512@d32768 335.13 332.27 0.99
MI60 / MI50 llama 8B Q4_0 256 pp512@d32768 351.75 349.71 0.99
MI60 / MI50 llama 8B Q4_0 512 pp512@d32768 357.18 355.12 0.99
MI100 llama 8B Q4_0 1 pp512@d32768 77.78 82.66 1.06
MI100 llama 8B Q4_0 2 pp512@d32768 133.33 139.16 1.04
MI100 llama 8B Q4_0 4 pp512@d32768 164.44 169.21 1.03
MI100 llama 8B Q4_0 8 pp512@d32768 232.70 236.51 1.02
MI100 llama 8B Q4_0 16 pp512@d32768 424.09 431.27 1.02
MI100 llama 8B Q4_0 32 pp512@d32768 559.43 563.32 1.01
MI100 llama 8B Q4_0 64 pp512@d32768 648.34 648.77 1.00
MI100 llama 8B Q4_0 128 pp512@d32768 671.01 668.83 1.00
MI100 llama 8B Q4_0 256 pp512@d32768 696.50 692.00 0.99
MI100 llama 8B Q4_0 512 pp512@d32768 706.38 700.32 0.99
P40 llama 8B Q4_0 1 pp512@d32768 31.00 32.45 1.05
P40 llama 8B Q4_0 2 pp512@d32768 59.14 61.75 1.04
P40 llama 8B Q4_0 4 pp512@d32768 87.36 89.87 1.03
P40 llama 8B Q4_0 8 pp512@d32768 122.68 122.31 1.00
P40 llama 8B Q4_0 16 pp512@d32768 178.33 175.34 0.98
P40 llama 8B Q4_0 32 pp512@d32768 189.92 190.07 1.00
P40 llama 8B Q4_0 64 pp512@d32768 209.02 208.27 1.00
P40 llama 8B Q4_0 128 pp512@d32768 217.96 217.49 1.00
P40 llama 8B Q4_0 256 pp512@d32768 223.15 222.81 1.00
P40 llama 8B Q4_0 512 pp512@d32768 219.45 219.48 1.00
Radeon 8060S Graphics llama 8B Q4_0 1 pp512@d32768 23.92 24.10 1.01
Radeon 8060S Graphics llama 8B Q4_0 2 pp512@d32768 43.49 43.68 1.00
Radeon 8060S Graphics llama 8B Q4_0 4 pp512@d32768 77.88 78.19 1.00
Radeon 8060S Graphics llama 8B Q4_0 8 pp512@d32768 108.82 96.17 0.88
Radeon 8060S Graphics llama 8B Q4_0 16 pp512@d32768 138.58 140.27 1.01
Radeon 8060S Graphics llama 8B Q4_0 32 pp512@d32768 151.39 152.96 1.01
Radeon 8060S Graphics llama 8B Q4_0 64 pp512@d32768 74.81 76.94 1.03
Radeon 8060S Graphics llama 8B Q4_0 128 pp512@d32768 101.46 102.30 1.01
Radeon 8060S Graphics llama 8B Q4_0 256 pp512@d32768 115.59 115.84 1.00
Radeon 8060S Graphics llama 8B Q4_0 512 pp512@d32768 117.65 118.57 1.01
RTX 3090 llama 8B Q4_0 1 pp512@d32768 87.54 92.96 1.06
RTX 3090 llama 8B Q4_0 2 pp512@d32768 160.48 170.31 1.06
RTX 3090 llama 8B Q4_0 4 pp512@d32768 293.48 303.46 1.03
RTX 3090 llama 8B Q4_0 8 pp512@d32768 429.51 439.54 1.02
RTX 3090 llama 8B Q4_0 16 pp512@d32768 844.62 874.15 1.03
RTX 3090 llama 8B Q4_0 32 pp512@d32768 1184.30 1194.99 1.01
RTX 3090 llama 8B Q4_0 64 pp512@d32768 1491.70 1495.43 1.00
RTX 3090 llama 8B Q4_0 128 pp512@d32768 1612.42 1617.77 1.00
RTX 3090 llama 8B Q4_0 256 pp512@d32768 1716.96 1697.92 0.99
RTX 3090 llama 8B Q4_0 512 pp512@d32768 1470.93 1448.12 0.98
RTX 4090 llama 8B Q4_0 1 pp512@d32768 98.14 102.76 1.05
RTX 4090 llama 8B Q4_0 2 pp512@d32768 178.13 190.39 1.07
RTX 4090 llama 8B Q4_0 4 pp512@d32768 349.90 366.50 1.05
RTX 4090 llama 8B Q4_0 8 pp512@d32768 618.83 646.33 1.04
RTX 4090 llama 8B Q4_0 16 pp512@d32768 1095.54 1140.84 1.04
RTX 4090 llama 8B Q4_0 32 pp512@d32768 2007.89 2051.87 1.02
RTX 4090 llama 8B Q4_0 64 pp512@d32768 3091.16 3089.09 1.00
RTX 4090 llama 8B Q4_0 128 pp512@d32768 3188.55 3095.61 0.97
RTX 4090 llama 8B Q4_0 256 pp512@d32768 2961.18 2892.63 0.98
RTX 4090 llama 8B Q4_0 512 pp512@d32768 2464.56 2431.25 0.99
RTX 5090 llama 8B Q4_0 1 pp512@d32768 155.78 167.41 1.07
RTX 5090 llama 8B Q4_0 2 pp512@d32768 239.31 269.27 1.13
RTX 5090 llama 8B Q4_0 4 pp512@d32768 461.48 486.56 1.05
RTX 5090 llama 8B Q4_0 8 pp512@d32768 780.64 810.10 1.04
RTX 5090 llama 8B Q4_0 16 pp512@d32768 1381.19 1408.61 1.02
RTX 5090 llama 8B Q4_0 32 pp512@d32768 2253.55 2308.20 1.02
RTX 5090 llama 8B Q4_0 64 pp512@d32768 2827.63 2828.64 1.00
RTX 5090 llama 8B Q4_0 128 pp512@d32768 3009.14 3075.67 1.02
RTX 5090 llama 8B Q4_0 256 pp512@d32768 3078.24 2981.31 0.97
RTX 5090 llama 8B Q4_0 512 pp512@d32768 2698.04 2640.36 0.98
RX 6800 llama 8B Q4_0 1 pp512@d32768 42.25 44.60 1.06
RX 6800 llama 8B Q4_0 2 pp512@d32768 77.43 81.42 1.05
RX 6800 llama 8B Q4_0 4 pp512@d32768 105.08 108.86 1.04
RX 6800 llama 8B Q4_0 8 pp512@d32768 140.43 140.94 1.00
RX 6800 llama 8B Q4_0 16 pp512@d32768 173.28 175.32 1.01
RX 6800 llama 8B Q4_0 32 pp512@d32768 209.55 210.72 1.01
RX 6800 llama 8B Q4_0 64 pp512@d32768 235.46 235.80 1.00
RX 6800 llama 8B Q4_0 128 pp512@d32768 262.63 262.85 1.00
RX 6800 llama 8B Q4_0 256 pp512@d32768 274.40 274.65 1.00
RX 6800 llama 8B Q4_0 512 pp512@d32768 275.25 274.63 1.00
RX 9060 XT llama 8B Q4_0 1 pp512@d32768 25.67 29.58 1.15
RX 9060 XT llama 8B Q4_0 2 pp512@d32768 49.98 57.25 1.15
RX 9060 XT llama 8B Q4_0 4 pp512@d32768 85.18 97.39 1.14
RX 9060 XT llama 8B Q4_0 8 pp512@d32768 111.87 104.18 0.93
RX 9060 XT llama 8B Q4_0 16 pp512@d32768 162.98 172.35 1.06
RX 9060 XT llama 8B Q4_0 32 pp512@d32768 190.29 195.63 1.03
RX 9060 XT llama 8B Q4_0 64 pp512@d32768 288.59 291.34 1.01
RX 9060 XT llama 8B Q4_0 128 pp512@d32768 322.67 325.96 1.01
RX 9060 XT llama 8B Q4_0 256 pp512@d32768 348.31 351.01 1.01
RX 9060 XT llama 8B Q4_0 512 pp512@d32768 349.45 350.95 1.00

The performance numbers assume that the KQ mask is no longer being padded. This change is also in this PR. I don't have a good overview of which other backends maybe still need support for this change and whether or not it should be reverted prior to merging.

@loci-dev loci-dev force-pushed the upstream-PR17505-branch_JohannesGaessler-cuda-fa-mma-update-5 branch from 6455c6d to 2ef0c5f Compare November 25, 2025 23:35
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Performance Analysis Summary: PR #328

PR Title: CUDA: Generalized MMA FlashAttention, Add Volta Support
Scope: CUDA FlashAttention kernel refactoring with Volta tensor core support


Overview

This PR refactors CUDA FlashAttention kernels to add Volta tensor core support and remove mask padding requirements. The changes affect 10 files with 935 additions and 735 deletions, primarily in CUDA kernel implementations. Performance metrics show negligible impact on core inference functions, with changes concentrated in utility functions and template infrastructure.

Key Findings

Performance-Critical Functions Impact

The analysis reveals no meaningful changes to core inference functions. The top 10 functions by Response Time change are utility functions in standard library and helper code:

Functions with increased Response Time:

  • begin in libmtmd.so: +176 ns (210% change, from 84 ns to 261 ns)
  • operator= in libllama.so: +71 ns (9% change, from 766 ns to 837 ns)
  • add_kv in libllama.so: +4 ns (17% change, from 25 ns to 29 ns)
  • stbi__setup_jpeg in libmtmd.so: +3 ns (19% change, from 18 ns to 21 ns)

Functions with decreased Response Time:

  • back_inserter in libllama.so: -180 ns (66% reduction, from 272 ns to 92 ns)
  • _S_max_size in libllama.so: -208 ns (56% reduction, from 371 ns to 162 ns)
  • rbegin in libllama.so: -116 ns (38% reduction, from 304 ns to 188 ns)

None of these functions are in the tokenization or inference critical path (llama_decode, llama_encode, llama_tokenize, llama_model_load).

Tokens Per Second Impact

No impact on inference throughput. The core inference functions (llama_decode, llama_encode, llama_tokenize) show no Response Time or Throughput changes in this version. The modified CUDA kernels are template-based infrastructure changes that do not alter the execution path for existing GPU architectures. The performance benchmarks in the PR description show improvements ranging from 1.05x to 2.97x on V100 GPUs for various batch sizes, indicating the changes optimize GPU execution without affecting CPU inference paths.

Power Consumption Analysis

Power consumption changes are minimal across all binaries:

  • build.bin.libmtmd.so: +0.13% (+228 nJ)
  • build.bin.libllama.so: -0.02% (-52 nJ)
  • build.bin.libggml-base.so: -0.07% (-52 nJ)
  • All other binaries: 0.0% change

The power consumption variations are within measurement noise and reflect the minor changes in utility function execution times rather than algorithmic modifications.

Code Changes Analysis

Primary modifications:

  1. Mask padding removal: Changed GGML_KQ_MASK_PAD from 64 to 1, eliminating unnecessary padding overhead. The kernels now use modulo operations (fastmodulo) to handle non-padded masks without conditional branches.

  2. Volta tensor core support: Added DATA_SPLIT_MIRRORED tile types and Volta-specific MMA instructions. The tile structure now supports different data layouts across warp subgroups for Volta architecture (tile<8, 4, half2>).

  3. Configuration refactoring: Replaced template-based fattn_mma_f16_config structs with runtime configuration functions that pack parameters into uint32_t. This addresses ROCm compiler limitations with __launch_bounds__ templating.

  4. Out-of-bounds checking: Added oob_check template parameter to handle cases where ne11 % nbatch_fa != 0, zeroing out-of-bounds values instead of requiring padding.

  5. Type parameter changes: Changed ne01 from int32_t to uint3 for fast division support, and mask from half2* to half* for finer-grained access.

Impact on codebase:

The changes maintain backward compatibility for Turing and Ampere architectures while extending support to Volta. The refactoring consolidates three kernel variants (tile, WMMA, MMA) toward a unified MMA implementation. The WMMA kernel is now restricted to AMD GPUs only (removed Volta from GGML_USE_WMMA_FATTN definition).

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Performance Analysis Summary

Project: llama.cpp
PR #328: CUDA FlashAttention Generalization and Volta Support
Scope: 10 files modified (+935/-735 lines)


Analysis Outcome

This PR introduces CUDA FlashAttention kernel refactoring targeting GPU inference optimization. The analyzed performance metrics compare versions unrelated to this PR's commit (2ef0c5f63d4ac4d1b2622ae8b69be9406262f0f4). The measured changes affect CPU-side STL operations in libmtmd.so and libllama.so, not GPU kernels.

Code Changes: This PR modifies CUDA kernel implementations for V100 tensor core support, removes mask padding requirements (64→1), and refactors MMA configuration from templates to runtime lookup. Changes are isolated to GPU execution paths and do not affect CPU inference or tokenization functions.

Performance Metrics Context: The measured regressions in begin (+177 ns throughput), operator= (+70 ns throughput), and _M_allocate_buckets (+64 ns throughput) are STL container operations unrelated to GPU kernels. These functions are not in the inference critical path for token generation.

Inference Impact: No changes detected in llama_decode, llama_encode, or llama_tokenize functions. CPU-based token generation remains unaffected. The PR targets GPU-accelerated attention computation, which is orthogonal to the measured CPU-side metrics.

Power Consumption: libmtmd.so shows +0.134% (+228 nJ) increase, libllama.so shows -0.023% (-52 nJ) decrease. Net change across binaries is +176 nJ, representing negligible power impact. Changes stem from STL operations, not inference kernels.

Key Findings:

The performance metrics and code changes are decoupled. PR #328 implements GPU kernel optimizations (V100 support, mask handling improvements) that do not intersect with the measured CPU-side STL performance variations. The measured changes in iterator operations, memory allocation, and string handling are artifacts of different code paths or compiler optimizations unrelated to this PR's CUDA kernel modifications.

For GPU inference workloads, this PR is expected to improve V100 performance significantly while maintaining stability on Turing+ architectures based on the PR's benchmark data. CPU inference paths remain unchanged.

@loci-dev loci-dev force-pushed the main branch 13 times, most recently from aaa8a85 to 9239ee7 Compare November 28, 2025 14:08
@loci-dev loci-dev force-pushed the upstream-PR17505-branch_JohannesGaessler-cuda-fa-mma-update-5 branch from 2ef0c5f to 301ae30 Compare November 28, 2025 16:39
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Explore the complete analysis inside the Version Insights

Performance Analysis Summary: PR #328 CUDA FlashAttention Optimization

Overview

PR #328 introduces CUDA FlashAttention enhancements targeting GPU inference optimization. The changes span 10 files with 938 additions and 738 deletions, primarily affecting CUDA kernel implementations. This analysis focuses on CPU-side performance metrics from static analysis, which show minimal impact on core inference paths.

Key Findings

Performance-Critical Functions Impact

The static analysis identified performance variations in STL container operations within libllama.so and libmtmd.so binaries. However, these functions are not in the critical inference path:

libllama.so STL Operations:

  • std::vector<std::pair<std::wstring, std::wstring>>::end(): Response time increased 113 ns (82 ns → 195 ns)
  • std::vector<llm_symbol>::end(): Response time increased 32 ns (50 ns → 82 ns)
  • std::back_inserter<std::vector<double>>(): Response time increased 32 ns (60 ns → 92 ns)

libmtmd.so Audio Functions:

  • ma_dr_flac__on_seek_memory(): Response time increased 24 ns (188 ns → 212 ns)
  • ma_dr_wav__on_seek_memory_write(): Response time increased 25 ns (233 ns → 259 ns)

These functions are utility operations for tokenization metadata and multimedia processing, not direct inference execution. The absolute changes are measured in nanoseconds, representing negligible overhead.

Inference Performance Impact

Critical Finding: No core inference functions (llama_decode, llama_encode, llama_tokenize) show performance changes in the static analysis. The PR targets CUDA GPU kernels, which operate independently from CPU-side tokenization and model execution measured in this analysis.

Tokens per Second Projection: Based on the reference that 2 ms slower llama_decode causes 7% TPS reduction, the observed nanosecond-level changes in non-inference functions translate to unmeasurable TPS impact. The STL container operations occur during setup/teardown phases, not per-token processing.

Impacted Functions for Inference: None identified in CPU analysis. GPU kernel improvements (1.06-2.97x speedup on V100 per PR benchmarks) occur in CUDA code not captured by CPU binary analysis.

Power Consumption Analysis

libmtmd.so: Increased 508 nJ (130,247 nJ → 130,755 nJ), representing +0.39% change. This binary handles multimedia operations (audio decoding via miniaudio library), not core LLM inference.

libllama.so: Decreased 54 nJ (193,066 nJ → 193,012 nJ), representing -0.028% change. The reduction indicates slightly improved efficiency in the core library despite individual function variations.

Other Binaries: All other binaries (llama-bench, llama-quantize, llama-run, libggml.so, etc.) show 0.0% power consumption change, confirming the modifications are isolated to specific components.

Code Change Analysis

The PR implements:

  1. Volta tensor core support via generalized MMA kernel architecture
  2. Mask padding reduction (GGML_KQ_MASK_PAD: 64 → 1) for memory efficiency
  3. Out-of-bounds checking for flexible KV cache lengths
  4. Configuration system refactoring using macro-based packing

These changes target GPU execution paths. The CPU-side STL regressions observed in static analysis stem from compiler optimization differences or structure layout changes, not algorithmic modifications. The wide string and symbol vector operations showing degradation are used in vocabulary management and Unicode handling during model initialization, not per-token inference loops.

Synthesis

The static analysis captures CPU binary performance while the PR optimizes GPU kernels. The observed nanosecond-level variations in STL containers and audio functions do not affect inference throughput. The power consumption changes are minimal across all binaries, with libllama.so showing slight improvement. For GPU inference workloads (the PR's target), the CUDA kernel optimizations deliver substantial speedups (up to 2.97x on Volta) without measurable CPU-side regression in core inference functions.

@loci-dev loci-dev force-pushed the main branch 2 times, most recently from 9a74048 to af6127b Compare November 28, 2025 20:09
@loci-dev loci-dev force-pushed the main branch 30 times, most recently from 4f731df to 8e6f6e8 Compare December 12, 2025 15:09
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