ggml-org/llama.cpp b11335

on GitHub

cuda : route sm70 to the Turing MMVQ nwarps table (#29753)

• cuda : route sm70 to the Turing MMVQ nwarps table

Volta (sm_70) has no MMVQ parameter table of its own and falls through
to GENERIC, which launches K-quant batch-1 decode (ncols_dst == 1) at
nwarps=4. sm_70 shares TURING's tuning: the K-quant vec_dot prefers
nwarps=2 there. Route sm_70 to the existing MMVQ_PARAMETERS_TURING
table in both the device and the host table selector.

Measured on one Tesla V100 32GB PCIe (PG500-216, driver 580.178.04,
CUDA 12.0.140) with Qwen3.8-27B Q4_K_M, tg128, interleaved A/B in 6
ABBA blocks with paired per-block deltas: +1.091 t/s = +3.17 %
(t = +49.0, all six per-block deltas positive); perplexity
bit-identical (6.3697 +/- 0.04066 both builds, wiki.test.raw). The
patched build's K-quant mul_mat_vec_q kernels launch at nwarps=2
(cubin EIATTR_MAX_THREADS) while Q4_0/Q8_0 stay at nwarps=4, and the
same measurement on the September master base gave +3.84 % (t = 85).

The tuning originates from the V100-focused fork anyei/llamacpp-v100
(MIT), commit b912d1b1e, which carries a dedicated
MMVQ_PARAMETERS_VOLTA table; a cubin-level comparison confirmed that
routing sm_70 to the existing TURING table is equivalent for the
K-quant batch-1 path this change affects, so this is the minimal
2-line form. anyei/llamacpp-v100@b912d1b1e

Original-patch-by: anyei angelyoelroblesmercedes@gmail.com

• Update ggml/src/ggml-cuda/mmvq.cu

Co-authored-by: tkittich tkittich@gmail.com
Co-authored-by: Johannes Gäßler johannesg@5d6.de