Files
ktransformers/kt-kernel/examples/test_k2_write_buffer.py
2025-12-17 19:46:32 +08:00

269 lines
11 KiB
Python

import os
import sys
import time
import torch
import numpy as np
# Ensure we can import the local extension
# REPO_ROOT = os.path.abspath(os.path.join(os.path.dirname(__file__), "../"))
# if REPO_ROOT not in sys.path:
# sys.path.insert(0, REPO_ROOT)
from kt_kernel import kt_kernel_ext
from kt_kernel_ext import CPUInfer
def make_cpu_infer(thread_num=80):
return CPUInfer(thread_num)
def build_config(cpuinfer, expert_num, num_experts_per_tok, hidden_size, intermediate_size, group_size):
cfg = kt_kernel_ext.moe.MOEConfig(expert_num, num_experts_per_tok, hidden_size, intermediate_size)
cfg.max_len = 1
cfg.quant_config.bits = 4
cfg.quant_config.group_size = group_size
cfg.quant_config.zero_point = False
cfg.pool = cpuinfer.backend_
return cfg
def allocate_weights(expert_num, hidden_size, intermediate_size, group_size):
# packed int4 weights: 2 values per byte
per_mat_weight_bytes = (hidden_size * intermediate_size) // 2
per_mat_scale_elems = (hidden_size * intermediate_size) // group_size
gate_q = torch.randint(0, 256, (expert_num * per_mat_weight_bytes,), dtype=torch.uint8)
up_q = torch.randint(0, 256, (expert_num * per_mat_weight_bytes,), dtype=torch.uint8)
down_q = torch.randint(0, 256, (expert_num * per_mat_weight_bytes,), dtype=torch.uint8)
gate_scale = torch.randn(expert_num * per_mat_scale_elems, dtype=torch.bfloat16)
up_scale = torch.randn(expert_num * per_mat_scale_elems, dtype=torch.bfloat16)
down_scale = torch.randn(expert_num * per_mat_scale_elems, dtype=torch.bfloat16)
return (
gate_q,
up_q,
down_q,
gate_scale,
up_scale,
down_scale,
per_mat_weight_bytes,
per_mat_scale_elems,
)
def main():
torch.manual_seed(123)
expert_num = 256 # Total experts
gpu_experts = expert_num # Number of experts on GPU
gpu_tp_count = 2 # Number of TP parts
num_experts_per_tok = 8
hidden_size = 7168
intermediate_size = 2048
group_size = 32
cpuinfer = make_cpu_infer()
cfg = build_config(cpuinfer, expert_num, num_experts_per_tok, hidden_size, intermediate_size, group_size)
(
gate_q,
up_q,
down_q,
gate_scale,
up_scale,
down_scale,
per_mat_weight_bytes,
per_mat_scale_elems,
) = allocate_weights(expert_num, hidden_size, intermediate_size, group_size)
cfg.gate_proj = gate_q.data_ptr()
cfg.up_proj = up_q.data_ptr()
cfg.down_proj = down_q.data_ptr()
cfg.gate_scale = gate_scale.data_ptr()
cfg.up_scale = up_scale.data_ptr()
cfg.down_scale = down_scale.data_ptr()
moe = kt_kernel_ext.moe.AMXInt4_KGroup_MOE(cfg)
physical_to_logical_map = torch.arange(expert_num, dtype=torch.int64, device="cpu").contiguous()
cpuinfer.submit(moe.load_weights_task(physical_to_logical_map.data_ptr()))
cpuinfer.sync()
# TP configuration
# Since weights are col-major, we can directly divide the total size by tp_count
# Each matrix is divided into gpu_tp_count parts in memory order
# Calculate sizes per TP part (direct division since col-major)
weight_bytes_per_expert_per_tp = per_mat_weight_bytes // gpu_tp_count
scale_elems_per_expert_per_tp = per_mat_scale_elems // gpu_tp_count
# Total sizes for all gpu_experts
total_weight_bytes_per_tp = gpu_experts * weight_bytes_per_expert_per_tp
total_scale_elems_per_tp = gpu_experts * scale_elems_per_expert_per_tp
# Create buffer lists for w13 (gate+up) and w2 (down)
w13_weight_bufs = []
w13_scale_bufs = []
w2_weight_bufs = []
w2_scale_bufs = []
for tp_idx in range(gpu_tp_count):
# w13 combines gate and up, so needs 2x the size
w13_weight_bufs.append(torch.empty(2 * total_weight_bytes_per_tp, dtype=torch.uint8))
w13_scale_bufs.append(torch.empty(2 * total_scale_elems_per_tp, dtype=torch.bfloat16))
w2_weight_bufs.append(torch.empty(total_weight_bytes_per_tp, dtype=torch.uint8))
w2_scale_bufs.append(torch.empty(total_scale_elems_per_tp, dtype=torch.bfloat16))
# Get data pointers for all buffers
w13_weight_ptrs = [buf.data_ptr() for buf in w13_weight_bufs]
w13_scale_ptrs = [buf.data_ptr() for buf in w13_scale_bufs]
w2_weight_ptrs = [buf.data_ptr() for buf in w2_weight_bufs]
w2_scale_ptrs = [buf.data_ptr() for buf in w2_scale_bufs]
print(f"Total experts: {expert_num}, GPU experts: {gpu_experts}")
print(f"GPU TP count: {gpu_tp_count}")
print(f"Original per matrix weight bytes: {per_mat_weight_bytes}")
print(f"Original per matrix scale elements: {per_mat_scale_elems}")
print(f"Weight bytes per expert per TP: {weight_bytes_per_expert_per_tp}")
print(f"Scale elements per expert per TP: {scale_elems_per_expert_per_tp}")
print(f"Total weight bytes per TP (w13): {2 * total_weight_bytes_per_tp}")
print(f"Total weight bytes per TP (w2): {total_weight_bytes_per_tp}")
print(f"Total scale elements per TP (w13): {2 * total_scale_elems_per_tp}")
print(f"Total scale elements per TP (w2): {total_scale_elems_per_tp}")
for i in range(5):
cpuinfer.submit(
moe.write_weight_scale_to_buffer_task(
gpu_tp_count=gpu_tp_count,
gpu_experts_num=gpu_experts,
w13_weight_ptrs=w13_weight_ptrs,
w13_scale_ptrs=w13_scale_ptrs,
w2_weight_ptrs=w2_weight_ptrs,
w2_scale_ptrs=w2_scale_ptrs,
)
)
cpuinfer.sync()
begin_time = time.perf_counter_ns()
cpuinfer.submit(
moe.write_weight_scale_to_buffer_task(
gpu_tp_count=gpu_tp_count,
gpu_experts_num=gpu_experts,
w13_weight_ptrs=w13_weight_ptrs,
w13_scale_ptrs=w13_scale_ptrs,
w2_weight_ptrs=w2_weight_ptrs,
w2_scale_ptrs=w2_scale_ptrs,
)
)
cpuinfer.sync()
end_time = time.perf_counter_ns()
elapsed_ms = (end_time - begin_time) / 1000000
total_weights = hidden_size * intermediate_size * expert_num * 3
total_bytes = total_weights // group_size + total_weights // 2
print(f"write_weight_scale_to_buffer time: {elapsed_ms:.2f} ms")
print(f"Throughput: {total_bytes / (elapsed_ms * 1e6):.2f} GB/s")
def split_expert_tensor(tensor, chunk):
"""Split tensor by experts"""
return [tensor[i * chunk : (i + 1) * chunk] for i in range(expert_num)]
# Split by experts first
gate_q_experts = split_expert_tensor(gate_q, per_mat_weight_bytes)
up_q_experts = split_expert_tensor(up_q, per_mat_weight_bytes)
down_q_experts = split_expert_tensor(down_q, per_mat_weight_bytes)
gate_scale_experts = split_expert_tensor(gate_scale, per_mat_scale_elems)
up_scale_experts = split_expert_tensor(up_scale, per_mat_scale_elems)
down_scale_experts = split_expert_tensor(down_scale, per_mat_scale_elems)
# CPU TP count is always 2 in this test setup (one TP per NUMA node)
cpu_tp_count = 2
# Verify buffers for each TP part
for tp_idx in range(gpu_tp_count):
expected_w13_weights = []
expected_w13_scales = []
expected_w2_weights = []
expected_w2_scales = []
weight13_per_tp = per_mat_weight_bytes // gpu_tp_count
scale13_per_tp = per_mat_scale_elems // gpu_tp_count
# Process each GPU expert
for expert_idx in range(gpu_experts):
# For w13 (gate and up), the slicing is straightforward
start_weight = tp_idx * weight13_per_tp
end_weight = (tp_idx + 1) * weight13_per_tp
start_scale = tp_idx * scale13_per_tp
end_scale = (tp_idx + 1) * scale13_per_tp
# Gate
gate_weight_tp = gate_q_experts[expert_idx][start_weight:end_weight]
gate_scale_tp = gate_scale_experts[expert_idx][start_scale:end_scale]
# Up
up_weight_tp = up_q_experts[expert_idx][start_weight:end_weight]
up_scale_tp = up_scale_experts[expert_idx][start_scale:end_scale]
# Down matrix needs special handling because it's sliced column-wise
# We need to reconstruct it from column slices
down_weight_tp_parts = []
down_scale_tp_parts = []
# Iterate through each column to extract the corresponding parts
for col_idx in range(hidden_size):
col_weight_start = col_idx * (intermediate_size // 2)
col_scale_start = col_idx * (intermediate_size // group_size)
# Direct mapping: each CPU TP corresponds to a GPU TP
tp_slice_weight_size = (intermediate_size // gpu_tp_count) // 2
tp_slice_scale_size = (intermediate_size // gpu_tp_count) // group_size
tp_weight_offset = col_weight_start + tp_idx * tp_slice_weight_size
tp_scale_offset = col_scale_start + tp_idx * tp_slice_scale_size
down_weight_tp_parts.append(
down_q_experts[expert_idx][tp_weight_offset : tp_weight_offset + tp_slice_weight_size]
)
down_scale_tp_parts.append(
down_scale_experts[expert_idx][tp_scale_offset : tp_scale_offset + tp_slice_scale_size]
)
# Concatenate all column slices for this TP
down_weight_tp = torch.cat(down_weight_tp_parts)
down_scale_tp = torch.cat(down_scale_tp_parts)
expected_w13_weights.append(gate_weight_tp)
expected_w13_weights.append(up_weight_tp)
expected_w13_scales.append(gate_scale_tp)
expected_w13_scales.append(up_scale_tp)
expected_w2_weights.append(down_weight_tp)
expected_w2_scales.append(down_scale_tp)
# Concatenate all experts for this TP part
expected_w13_weight = torch.cat(expected_w13_weights)
expected_w13_scale = torch.cat(expected_w13_scales)
expected_w2_weight = torch.cat(expected_w2_weights)
expected_w2_scale = torch.cat(expected_w2_scales)
print(f"=== Checking TP part {tp_idx} ===")
# Assert all checks pass
assert torch.equal(w13_weight_bufs[tp_idx], expected_w13_weight), f"w13 weight bytes mismatch for TP {tp_idx}"
assert torch.allclose(w13_scale_bufs[tp_idx], expected_w13_scale), f"w13 scale values mismatch for TP {tp_idx}"
assert torch.equal(w2_weight_bufs[tp_idx], expected_w2_weight), f"w2 weight bytes mismatch for TP {tp_idx}"
assert torch.allclose(w2_scale_bufs[tp_idx], expected_w2_scale), f"w2 scale values mismatch for TP {tp_idx}"
print(
f"\n✓ write_weight_scale_to_buffer passed: extracted {gpu_experts} GPU experts across {gpu_tp_count} TP parts from total {expert_num} experts"
)
if __name__ == "__main__":
main()