Skip to content

Improve utilization (and tg t/s) by reducing K_QUANTS_PER_ITERATION to 1 on DMMV path #25063

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
ggerganov merged 4 commits into from
Jul 7, 2026
Merged

Improve utilization (and tg t/s) by reducing K_QUANTS_PER_ITERATION to 1 on DMMV path #25063

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
0c4df1c
sycl: add supported types to ggml_sycl_supports_reorder_dmmv
malsbat Jun 24, 2026
0fab1f3
sycl: set K_QUANTS_PER_ITERATION=1 to improve utilization
malsbat Jun 25, 2026
af50310
sycl: replace QK_WARP_SIZE with WARP_SIZE for QK_5
malsbat Jun 26, 2026
47a9754
sycl: add missing types to ggml_backend_sycl_buffer_init_tensor
malsbat Jun 26, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
27 changes: 15 additions & 12 deletions ggml/src/ggml-sycl/dmmv.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -680,14 +680,14 @@ static void dequantize_mul_mat_vec_q4_k(const void *__restrict__ vx,
q16[2] = q2[0] & 0x0f0f;
q16[3] = q2[0] & 0xf0f0;

float4 s = {0.f, 0.f, 0.f, 0.f};
sycl::float4 s = {0.f, 0.f, 0.f, 0.f};
float smin = 0;
for (int l = 0; l < 2; ++l) {
s.x += y1[l] * q4[l+0]; s.y += y1[l+32] * q4[l+2];
s.z += y2[l] * q4[l+4]; s.w += y2[l+32] * q4[l+6];
s.x() += y1[l] * q4[l+0]; s.y() += y1[l+32] * q4[l+2];
s.z() += y2[l] * q4[l+4]; s.w() += y2[l+32] * q4[l+6];
smin += y1[l] * sc[2] + y1[l+32] * sc[3] + y2[l] * sc[6] + y2[l+32] * sc[7];
}
tmp += dall * (s.x * sc[0] + s.y * sc[1] * 1.f/16.f + s.z * sc[4] + s.w * sc[5] * 1.f/16.f) - dmin * smin;
tmp += dall * (s.x() * sc[0] + s.y() * sc[1] * 1.f/16.f + s.z() * sc[4] + s.w() * sc[5] * 1.f/16.f) - dmin * smin;
#endif
}

Expand Down Expand Up @@ -835,14 +835,14 @@ static void dequantize_mul_mat_vec_q4_k_reorder(const void *__restrict__ vx,
q16[2] = q2[0] & 0x0f0f;
q16[3] = q2[0] & 0xf0f0;

float4 s = {0.f, 0.f, 0.f, 0.f};
sycl::float4 s = {0.f, 0.f, 0.f, 0.f};
float smin = 0;
for (int l = 0; l < 2; ++l) {
s.x += y1[l] * q4[l+0]; s.y += y1[l+32] * q4[l+2];
s.z += y2[l] * q4[l+4]; s.w += y2[l+32] * q4[l+6];
s.x() += y1[l] * q4[l+0]; s.y() += y1[l+32] * q4[l+2];
s.z() += y2[l] * q4[l+4]; s.w() += y2[l+32] * q4[l+6];
smin += y1[l] * sc[2] + y1[l+32] * sc[3] + y2[l] * sc[6] + y2[l+32] * sc[7];
}
tmp += dall * (s.x * sc[0] + s.y * sc[1] * 1.f/16.f + s.z * sc[4] + s.w * sc[5] * 1.f/16.f) - dmin * smin;
tmp += dall * (s.x() * sc[0] + s.y() * sc[1] * 1.f/16.f + s.z() * sc[4] + s.w() * sc[5] * 1.f/16.f) - dmin * smin;
#endif
}

Expand Down Expand Up @@ -1126,7 +1126,7 @@ static void dequantize_mul_mat_vec_q5_k_reorder(const void *__restrict__ vx,

// sum up partial sums and write back result
#pragma unroll
for (int mask = QK_WARP_SIZE / 2; mask > 0; mask >>= 1) {
for (int mask = WARP_SIZE / 2; mask > 0; mask >>= 1) {
tmp +=
dpct::permute_sub_group_by_xor(item_ct1.get_sub_group(), tmp, mask);
}
Expand Down Expand Up @@ -1762,10 +1762,13 @@ static void dequantize_mul_mat_vec_q5_K_sycl_reorder(const void *vx, const float
const int nrows,
dpct::queue_ptr stream) {
GGML_ASSERT(ncols % QK_K == 0);
const sycl::range<3> block_dims(1, 1, QK_WARP_SIZE);
const int ny = 2 / K_QUANTS_PER_ITERATION;
const int block_num_y = (nrows + ny - 1) / ny;
const sycl::range<3> block_nums(1, 1, block_num_y);
const sycl::range<3> block_dims(1, ny, WARP_SIZE);
stream->parallel_for(
sycl::nd_range<3>(sycl::range<3>(1, 1, nrows) * block_dims, block_dims),
[=](sycl::nd_item<3> item_ct1) [[sycl::reqd_sub_group_size(QK_WARP_SIZE)]] {
sycl::nd_range<3>(block_nums * block_dims, block_dims),
[=](sycl::nd_item<3> item_ct1) [[sycl::reqd_sub_group_size(WARP_SIZE)]] {
dequantize_mul_mat_vec_q5_k_reorder(vx, y, dst, ncols, nrows, item_ct1);
});
}
Expand Down
6 changes: 6 additions & 0 deletions ggml/src/ggml-sycl/ggml-sycl.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -521,7 +521,9 @@ ggml_backend_sycl_buffer_init_tensor(ggml_backend_buffer_t buffer,
switch (tensor->type) {
case GGML_TYPE_Q4_0:
case GGML_TYPE_Q8_0:
case GGML_TYPE_Q3_K:
case GGML_TYPE_Q4_K:
case GGML_TYPE_Q5_K:
case GGML_TYPE_Q6_K:{
ggml_tensor_extra_gpu * extra = new ggml_tensor_extra_gpu{};
tensor->extra = extra;
Expand Down Expand Up @@ -3527,6 +3529,10 @@ inline bool ggml_sycl_supports_reorder_dmmv(enum ggml_type type) {
case GGML_TYPE_Q1_0:
case GGML_TYPE_Q4_0:
case GGML_TYPE_Q8_0:
case GGML_TYPE_Q3_K:
case GGML_TYPE_Q4_K:
case GGML_TYPE_Q5_K:
case GGML_TYPE_Q6_K:
return true;
default:
return false;
Expand Down
2 changes: 1 addition & 1 deletion ggml/src/ggml-sycl/presets.hpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -62,7 +62,7 @@
#endif

#ifndef K_QUANTS_PER_ITERATION
#define K_QUANTS_PER_ITERATION 2
#define K_QUANTS_PER_ITERATION 1
#else
static_assert(K_QUANTS_PER_ITERATION == 1 || K_QUANTS_PER_ITERATION == 2, "K_QUANTS_PER_ITERATION must be 1 or 2");
#endif
Expand Down
Loading