The new g64 model quantizes experts with group-size 64 (fmt=4): one f32
scale per 64 elements instead of per-row. This required changes across
the entire compute stack — CUDA kernel, engine dispatch, and dequant
helpers — plus a new fused gate+up kernel to recover the ~40% throughput
that the generic grouped path costs.
CUDA backend (backend_cuda.cu):
- ColiCudaTensor: add gs/ng fields for group-size metadata
- row_bytes/weight_at: fmt=4 uses same packed int4 layout as fmt=2
- quant_matmul: apply per-group scales (scales[o*ng+g]) for fmt=4,
matching the CPU matmul_i4_grouped accumulation exactly
- coli_cuda_tensor_upload: allocate O*ng scales (not O) for fmt=4,
store gs/ng on the tensor
- coli_cuda_tensor_update: handle grouped scales on refresh
- coli_cuda_tensor_free/tensor_bytes: VRAM accounting uses O*ng
- coli_cuda_expert_group: return 0 for fmt=4 (fall back to correct
per-expert path, since grouped_hidden/grouped_down kernels only
handle per-row scales)
- All 11 quant_matmul call sites updated to pass gs,ng
Engine (glm.c):
- qt_cuda_upload: pass t->gs to tensor_upload
- matmul dispatch (line 816): pass w->gs to coli_cuda_matmul
- kv_b shard upload: pass l->kv_b.gs
- kv_b shard rb computation: add fmt=4 case ((I+1)/2)
- embed_row: add fmt=4 branch with per-group scale dequant
- qt_addrow/qt_matvec_rows: add fmt=4 branches (CPU MLA absorption path)
- expert_gate_up: add matmul_i4_grouped_pair — fused gate+up for fmt=4
that reads x once instead of twice (+40% tok/s, 0.77 -> 1.08)
- run_text: prepend [gMASK]<sop> prefix for GLM models (#108 fix —
without it, PROMPT mode generates garbage on all GLM snapshots)
API (backend_cuda.h, backend_loader.c):
- coli_cuda_tensor_upload and coli_cuda_matmul signatures: add gs param
- Loader typedefs and wrappers thread gs through the DLL boundary
Tests:
- bench_tensor_core.cu, test_backend_cuda.cu, test_pipe_cuda.cu:
update all calls to new API signature (append gs=0 for non-grouped)
New tool: c/tools/diag_harness.py
- Comprehensive model diagnostic harness (system probe, correctness
smoke, deep PROFILE diagnostic, quality benchmarks via eval_glm.py,
throughput with/without MTP). Outputs JSON + Markdown reports.
Performance (GLM-5.2 744B g64 / RTX 5070 Ti / 32GB RAM):
broken CUDA: 0.05 tok/s (every tensor fell back to CPU)
fixed CUDA: 0.30 tok/s (6x — CUDA working)
+ full opt stack: 0.77 tok/s (CACHE_ROUTE + EXPERT_BUDGET)
+ fused grouped pair: 1.08 tok/s (+40% from gate+up fusion)
woolcoxm