[Quant Kernel] refactored per token group quant fp8 to support int8 up-to 2x faster (#4396)
This commit is contained in:
@@ -4,7 +4,7 @@ from typing import Tuple
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import torch
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import triton
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import triton.language as tl
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from sgl_kernel import sgl_per_token_group_quant_fp8
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from sgl_kernel import sgl_per_token_group_quant_fp8, sgl_per_token_group_quant_int8
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from sglang.srt.utils import is_hip
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@@ -13,7 +13,7 @@ fp8_type_ = torch.float8_e4m3fnuz if is_hip_ else torch.float8_e4m3fn
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@triton.jit
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def _per_token_group_quant_fp8(
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def _per_token_group_quant_8bit(
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# Pointers to inputs and output
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y_ptr,
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y_q_ptr,
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@@ -24,16 +24,15 @@ def _per_token_group_quant_fp8(
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N,
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# Avoid to divide zero
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eps,
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# Information for float8
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fp8_min,
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fp8_max,
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# Information for 8bit data type (int8 or fp8_type_)
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max_8bit,
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min_8bit,
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# Meta-parameters
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BLOCK: tl.constexpr,
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):
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"""A Triton-accelerated function to perform per-token-group quantization on a
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tensor.
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This function converts the tensor values into float8 values.
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This function converts the tensor values into 8bit values.
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"""
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# Map the program id to the row of X and Y it should compute.
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g_id = tl.program_id(0)
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@@ -47,30 +46,27 @@ def _per_token_group_quant_fp8(
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y = tl.load(y_ptr + cols, mask=mask, other=0.0).to(tl.float32)
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# Quant
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_absmax = tl.maximum(tl.max(tl.abs(y)), eps)
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y_s = _absmax / fp8_max
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y_q = tl.clamp(y / y_s, fp8_min, fp8_max).to(y_q_ptr.dtype.element_ty)
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y_s = _absmax / max_8bit
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y_q = tl.clamp(y / y_s, min_8bit, max_8bit).to(y_q_ptr.dtype.element_ty)
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tl.store(y_q_ptr + cols, y_q, mask=mask)
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tl.store(y_s_ptr, y_s)
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def triton_per_token_group_quant_fp8(
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def triton_per_token_group_quant_8bit(
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x: torch.Tensor,
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group_size: int,
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dst_dtype: torch.dtype,
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eps: float = 1e-10,
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dtype: torch.dtype = fp8_type_,
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) -> Tuple[torch.Tensor, torch.Tensor]:
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"""Function to perform per-token-group quantization on an input tensor `x`.
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It converts the tensor values into signed float8 values and returns the
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quantized tensor along with the scaling factor used for quantization.
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Args:
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x: The input tenosr with ndim >= 2.
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group_size: The group size used for quantization.
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eps: The minimum to avoid dividing zero.
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dtype: The dype of output tensor. Note that only `torch.float8_e4m3fn` is supported for now.
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Returns:
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Tuple[torch.Tensor, torch.Tensor]: The quantized tensor and the scaling factor for quantization.
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"""
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@@ -79,12 +75,16 @@ def triton_per_token_group_quant_fp8(
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), "the last dimension of `x` cannot be divisible by `group_size`"
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assert x.is_contiguous(), "`x` is not contiguous"
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finfo = torch.finfo(dtype)
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fp8_max = finfo.max
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if dst_dtype == torch.int8:
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iinfo = torch.iinfo(dst_dtype)
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max_8bit = iinfo.max
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min_8bit = iinfo.min
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else:
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finfo = torch.finfo(dst_dtype)
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max_8bit = finfo.max
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min_8bit = finfo.min
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fp8_min = -fp8_max
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x_q = torch.empty_like(x, device=x.device, dtype=dtype)
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x_q = torch.empty_like(x, device=x.device, dtype=dst_dtype)
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M = x.numel() // group_size
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N = group_size
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x_s = torch.empty(
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@@ -97,15 +97,15 @@ def triton_per_token_group_quant_fp8(
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# heuristics for number of warps
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num_warps = min(max(BLOCK // 256, 1), 8)
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num_stages = 1
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_per_token_group_quant_fp8[(M,)](
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_per_token_group_quant_8bit[(M,)](
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x,
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x_q,
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x_s,
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group_size,
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N,
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eps,
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fp8_min=fp8_min,
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fp8_max=fp8_max,
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max_8bit,
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min_8bit,
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BLOCK=BLOCK,
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num_warps=num_warps,
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num_stages=num_stages,
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@@ -114,50 +114,55 @@ def triton_per_token_group_quant_fp8(
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return x_q, x_s
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def sglang_per_token_group_quant_fp8(
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def sglang_per_token_group_quant_8bit(
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x: torch.Tensor,
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group_size: int,
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dst_dtype: torch.dtype,
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eps: float = 1e-10,
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dtype: torch.dtype = fp8_type_,
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):
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assert (
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x.shape[-1] % group_size == 0
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), "the last dimension of `x` cannot be divisible by `group_size`"
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assert x.is_contiguous(), "`x` is not contiguous"
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finfo = torch.finfo(dtype)
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fp8_max = finfo.max
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fp8_min = -fp8_max
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x_q = torch.empty_like(x, device=x.device, dtype=dtype)
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M = x.numel() // group_size
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N = group_size
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x_q = torch.empty_like(x, device=x.device, dtype=dst_dtype)
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x_s = torch.empty(
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x.shape[:-1] + (x.shape[-1] // group_size,),
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device=x.device,
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dtype=torch.float32,
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)
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sgl_per_token_group_quant_fp8(x, x_q, x_s, group_size, eps, fp8_min, fp8_max)
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if dst_dtype == torch.int8:
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iinfo = torch.iinfo(dst_dtype)
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int8_max = iinfo.max
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int8_min = iinfo.min
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sgl_per_token_group_quant_int8(x, x_q, x_s, group_size, eps, int8_min, int8_max)
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else:
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f8_info = torch.finfo(dst_dtype)
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fp8_max = f8_info.max
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fp8_min = f8_info.min
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sgl_per_token_group_quant_fp8(x, x_q, x_s, group_size, eps, fp8_min, fp8_max)
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return x_q, x_s
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def calculate_diff(batch_size, seq_len, group_size):
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dtype = torch.float16
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def calculate_diff(batch_size, seq_len, group_size, dst_dtype):
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device = torch.device("cuda")
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hidden_dim = group_size * 2
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x = torch.randn(batch_size, seq_len, hidden_dim, device=device, dtype=dtype)
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x = torch.randn(batch_size, seq_len, hidden_dim, device=device, dtype=torch.float16)
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x_q_triton, x_s_triton = triton_per_token_group_quant_fp8(x.clone(), group_size)
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x_q_sglang, x_s_sglang = sglang_per_token_group_quant_fp8(x.clone(), group_size)
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x_q_triton, x_s_triton = triton_per_token_group_quant_8bit(
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x.clone(), group_size, dst_dtype
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)
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x_q_sglang, x_s_sglang = sglang_per_token_group_quant_8bit(
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x.clone(), group_size, dst_dtype
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)
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if torch.allclose(
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x_q_triton.to(torch.float32), x_q_sglang.to(torch.float32), rtol=1e-3, atol=1e-5
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) and torch.allclose(x_s_triton, x_s_sglang, rtol=1e-3, atol=1e-5):
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print("✅ All implementations match")
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print(f"✅ {dst_dtype} implementations match")
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else:
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print("❌ Implementations differ")
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@@ -165,36 +170,40 @@ def calculate_diff(batch_size, seq_len, group_size):
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batch_size_range = [1, 2, 4, 8, 16, 32, 64]
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seq_len_range = [64, 128, 256, 512, 1024, 2048]
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group_size_range = [128] # For DeepSeek V3/R1
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dst_dtype_range = [torch.int8, fp8_type_]
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configs = list(itertools.product(batch_size_range, seq_len_range, group_size_range))
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configs = list(
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itertools.product(
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batch_size_range, seq_len_range, group_size_range, dst_dtype_range
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)
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)
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@triton.testing.perf_report(
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triton.testing.Benchmark(
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x_names=["batch_size", "seq_len", "group_size"],
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x_names=["batch_size", "seq_len", "group_size", "dst_dtype"],
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x_vals=configs,
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line_arg="provider",
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line_vals=["triton", "sglang"],
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line_names=["Triton", "SGL Kernel"],
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styles=[("blue", "-"), ("green", "-")],
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ylabel="us",
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plot_name="per-token-group-quant-fp8-performance",
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plot_name="per-token-group-quant-8bit-performance",
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args={},
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)
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)
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def benchmark(batch_size, seq_len, group_size, provider):
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dtype = torch.bfloat16
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def benchmark(batch_size, seq_len, group_size, dst_dtype, provider):
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device = torch.device("cuda")
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hidden_dim = 7168
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x = torch.randn(batch_size, seq_len, hidden_dim, device=device, dtype=dtype)
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x = torch.randn(batch_size, seq_len, hidden_dim, device=device, dtype=torch.float16)
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quantiles = [0.5, 0.2, 0.8]
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if provider == "triton":
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fn = lambda: triton_per_token_group_quant_fp8(x.clone(), group_size)
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fn = lambda: triton_per_token_group_quant_8bit(x.clone(), group_size, dst_dtype)
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elif provider == "sglang":
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fn = lambda: sglang_per_token_group_quant_fp8(x.clone(), group_size)
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fn = lambda: sglang_per_token_group_quant_8bit(x.clone(), group_size, dst_dtype)
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ms, min_ms, max_ms = triton.testing.do_bench(fn, quantiles=quantiles)
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@@ -203,6 +212,7 @@ def benchmark(batch_size, seq_len, group_size, provider):
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if __name__ == "__main__":
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calculate_diff(batch_size=4, seq_len=128, group_size=64)
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calculate_diff(batch_size=4, seq_len=128, group_size=64, dst_dtype=torch.int8)
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calculate_diff(batch_size=4, seq_len=128, group_size=64, dst_dtype=fp8_type_)
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benchmark.run(print_data=True)
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@@ -6,8 +6,6 @@
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#include "utils.h"
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using FP8_TYPE = c10::Float8_e4m3fn;
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__device__ __forceinline__ float GroupReduceMax(float val, const int tid) {
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unsigned mask = 0xffff;
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@@ -18,27 +16,28 @@ __device__ __forceinline__ float GroupReduceMax(float val, const int tid) {
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return val;
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}
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template <typename T, int GROUPS_PER_BLOCK = 16>
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__global__ void per_token_group_quant_fp8_kernel(
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template <typename T, typename DST_DTYPE>
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__global__ void per_token_group_quant_8bit_kernel(
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const T* __restrict__ input,
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void* __restrict__ output_q,
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float* __restrict__ output_s,
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const int group_size,
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const int num_groups,
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const int groups_per_block,
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const float eps,
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const float fp8_min,
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const float fp8_max) {
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const float min_8bit,
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const float max_8bit) {
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const int threads_per_group = 16;
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const int local_group_id = threadIdx.x / threads_per_group;
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const int lane_id = threadIdx.x % threads_per_group;
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const int block_group_id = blockIdx.x * GROUPS_PER_BLOCK;
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const int block_group_id = blockIdx.x * groups_per_block;
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const int block_group_offset = (block_group_id + local_group_id) * group_size;
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float local_absmax = eps;
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const T* group_input = input + block_group_offset;
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FP8_TYPE* group_output = static_cast<FP8_TYPE*>(output_q) + block_group_offset;
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DST_DTYPE* group_output = static_cast<DST_DTYPE*>(output_q) + block_group_offset;
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float* scale_output = output_s + (block_group_id + local_group_id);
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constexpr uint32_t vec_size = 16 / sizeof(T);
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@@ -60,7 +59,7 @@ __global__ void per_token_group_quant_fp8_kernel(
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local_absmax = GroupReduceMax(local_absmax, lane_id);
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const float y_s = local_absmax / fp8_max;
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const float y_s = local_absmax / max_8bit;
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if (lane_id == 0) {
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*scale_output = y_s;
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@@ -73,20 +72,20 @@ __global__ void per_token_group_quant_fp8_kernel(
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#pragma unroll
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for (uint32_t j = 0; j < vec_size; ++j) {
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float val = static_cast<float>(input_vec[j]);
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float q_val = fminf(fmaxf(val / y_s, fp8_min), fp8_max);
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group_output[i * vec_size + j] = FP8_TYPE(q_val);
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float q_val = fminf(fmaxf(val / y_s, min_8bit), max_8bit);
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group_output[i * vec_size + j] = DST_DTYPE(q_val);
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}
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}
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}
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void sgl_per_token_group_quant_fp8(
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void sgl_per_token_group_quant_8bit(
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torch::Tensor input,
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torch::Tensor output_q,
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torch::Tensor output_s,
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int64_t group_size,
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double eps,
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double fp8_min,
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double fp8_max) {
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double min_8bit,
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double max_8bit) {
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CHECK_INPUT(input);
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CHECK_INPUT(output_q);
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CHECK_INPUT(output_s);
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@@ -111,36 +110,58 @@ void sgl_per_token_group_quant_fp8(
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groups_per_block = 2;
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}
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#define LAUNCH_KERNEL(T, GPB) \
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do { \
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constexpr int GROUPS_PER_BLOCK = GPB; \
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dim3 grid((num_groups + GROUPS_PER_BLOCK - 1) / GROUPS_PER_BLOCK); \
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dim3 block(GROUPS_PER_BLOCK* THREADS_PER_GROUP); \
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per_token_group_quant_fp8_kernel<T, GROUPS_PER_BLOCK><<<grid, block, 0, stream>>>( \
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static_cast<T*>(input.data_ptr()), \
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output_q.data_ptr(), \
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static_cast<float*>(output_s.data_ptr()), \
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group_size, \
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num_groups, \
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(float)eps, \
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(float)fp8_min, \
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(float)fp8_max); \
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auto dst_type = output_q.scalar_type();
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const int num_blocks = num_groups / groups_per_block;
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const int num_threads = groups_per_block * THREADS_PER_GROUP;
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#define LAUNCH_KERNEL(T, DST_DTYPE) \
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do { \
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dim3 grid(num_blocks); \
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dim3 block(num_threads); \
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per_token_group_quant_8bit_kernel<T, DST_DTYPE><<<grid, block, 0, stream>>>( \
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static_cast<T*>(input.data_ptr()), \
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output_q.data_ptr(), \
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static_cast<float*>(output_s.data_ptr()), \
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group_size, \
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num_groups, \
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groups_per_block, \
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(float)eps, \
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(float)min_8bit, \
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(float)max_8bit); \
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} while (0)
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DISPATCH_PYTORCH_DTYPE_TO_CTYPE_FLOAT_FP16(input.scalar_type(), scalar_t, [&] {
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if (groups_per_block == 16) {
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LAUNCH_KERNEL(scalar_t, 16);
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} else if (groups_per_block == 8) {
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LAUNCH_KERNEL(scalar_t, 8);
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} else if (groups_per_block == 4) {
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LAUNCH_KERNEL(scalar_t, 4);
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} else if (groups_per_block == 2) {
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LAUNCH_KERNEL(scalar_t, 2);
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} else {
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LAUNCH_KERNEL(scalar_t, 1);
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if (dst_type == at::ScalarType::Char) {
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LAUNCH_KERNEL(scalar_t, int8_t);
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return true;
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} else if (dst_type == at::ScalarType::Float8_e4m3fn) {
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LAUNCH_KERNEL(scalar_t, c10::Float8_e4m3fn);
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return true;
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}
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return true;
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return false;
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});
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#undef LAUNCH_KERNEL
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}
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void sgl_per_token_group_quant_int8(
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torch::Tensor input,
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torch::Tensor output_q,
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torch::Tensor output_s,
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int64_t group_size,
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double eps,
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double int8_min,
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double int8_max) {
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sgl_per_token_group_quant_8bit(input, output_q, output_s, group_size, eps, int8_min, int8_max);
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}
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void sgl_per_token_group_quant_fp8(
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torch::Tensor input,
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torch::Tensor output_q,
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torch::Tensor output_s,
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int64_t group_size,
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double eps,
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double fp8_min,
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double fp8_max) {
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sgl_per_token_group_quant_8bit(input, output_q, output_s, group_size, eps, fp8_min, fp8_max);
|
||||
}
|
||||
@@ -98,6 +98,11 @@ TORCH_LIBRARY_EXPAND(sgl_kernel, m) {
|
||||
" float eps, float fp8_min, float fp8_max) -> ()");
|
||||
m.impl("sgl_per_token_group_quant_fp8", torch::kCUDA, &sgl_per_token_group_quant_fp8);
|
||||
|
||||
m.def(
|
||||
"sgl_per_token_group_quant_int8(Tensor input, Tensor output_q, Tensor output_s, int group_size,"
|
||||
" float eps, float int8_min, float int8_max) -> ()");
|
||||
m.impl("sgl_per_token_group_quant_int8", torch::kCUDA, &sgl_per_token_group_quant_int8);
|
||||
|
||||
m.def("sgl_per_tensor_quant_fp8(Tensor input, Tensor output_q, Tensor output_s, bool is_static) -> ()");
|
||||
m.impl("sgl_per_tensor_quant_fp8", torch::kCUDA, &sgl_per_tensor_quant_fp8);
|
||||
|
||||
|
||||
@@ -141,6 +141,14 @@ void sgl_per_token_group_quant_fp8(
|
||||
double eps,
|
||||
double fp8_min,
|
||||
double fp8_max);
|
||||
void sgl_per_token_group_quant_int8(
|
||||
at::Tensor input,
|
||||
at::Tensor output_q,
|
||||
at::Tensor output_s,
|
||||
int64_t group_size,
|
||||
double eps,
|
||||
double int8_min,
|
||||
double int8_max);
|
||||
void sgl_per_tensor_quant_fp8(at::Tensor input, at::Tensor output_q, at::Tensor output_s, bool is_static);
|
||||
void sgl_per_token_quant_fp8(at::Tensor input, at::Tensor output_q, at::Tensor output_s);
|
||||
void cublas_grouped_gemm(
|
||||
|
||||
@@ -31,6 +31,7 @@ from sgl_kernel.gemm import (
|
||||
int8_scaled_mm,
|
||||
sgl_per_tensor_quant_fp8,
|
||||
sgl_per_token_group_quant_fp8,
|
||||
sgl_per_token_group_quant_int8,
|
||||
sgl_per_token_quant_fp8,
|
||||
)
|
||||
from sgl_kernel.moe import moe_align_block_size, topk_softmax
|
||||
|
||||
@@ -96,6 +96,20 @@ def sgl_per_token_group_quant_fp8(
|
||||
)
|
||||
|
||||
|
||||
def sgl_per_token_group_quant_int8(
|
||||
input: torch.Tensor,
|
||||
output_q: torch.Tensor,
|
||||
output_s: torch.Tensor,
|
||||
group_size: int,
|
||||
eps: float,
|
||||
int8_min: float,
|
||||
int8_max: float,
|
||||
) -> None:
|
||||
torch.ops.sgl_kernel.sgl_per_token_group_quant_int8(
|
||||
input, output_q, output_s, group_size, eps, int8_min, int8_max
|
||||
)
|
||||
|
||||
|
||||
def sgl_per_tensor_quant_fp8(
|
||||
input: torch.Tensor,
|
||||
output_q: torch.Tensor,
|
||||
|
||||
@@ -153,7 +153,7 @@ sources = [
|
||||
"csrc/gemm/fp8_gemm_kernel.cu",
|
||||
"csrc/gemm/fp8_blockwise_gemm_kernel.cu",
|
||||
"csrc/gemm/int8_gemm_kernel.cu",
|
||||
"csrc/gemm/per_token_group_quant_fp8.cu",
|
||||
"csrc/gemm/per_token_group_quant_8bit.cu",
|
||||
"csrc/gemm/per_token_quant_fp8.cu",
|
||||
"csrc/gemm/per_tensor_quant_fp8.cu",
|
||||
"csrc/moe/moe_align_kernel.cu",
|
||||
|
||||
@@ -1,20 +1,20 @@
|
||||
import itertools
|
||||
from typing import Any, Dict, List, Optional, Tuple
|
||||
from typing import Tuple
|
||||
|
||||
import pytest
|
||||
import torch
|
||||
import triton
|
||||
import triton.language as tl
|
||||
from sgl_kernel import sgl_per_token_group_quant_fp8
|
||||
from sgl_kernel import sgl_per_token_group_quant_fp8, sgl_per_token_group_quant_int8
|
||||
|
||||
from sglang.srt.utils import get_device_core_count, get_device_name, is_hip
|
||||
from sglang.srt.utils import is_hip
|
||||
|
||||
is_hip_ = is_hip()
|
||||
fp8_type_ = torch.float8_e4m3fnuz if is_hip_ else torch.float8_e4m3fn
|
||||
|
||||
|
||||
@triton.jit
|
||||
def _per_token_group_quant_fp8(
|
||||
def _per_token_group_quant_8bit(
|
||||
# Pointers to inputs and output
|
||||
y_ptr,
|
||||
y_q_ptr,
|
||||
@@ -25,16 +25,15 @@ def _per_token_group_quant_fp8(
|
||||
N,
|
||||
# Avoid to divide zero
|
||||
eps,
|
||||
# Information for float8
|
||||
fp8_min,
|
||||
fp8_max,
|
||||
# Information for 8bit data type (int8 or fp8_type_)
|
||||
max_8bit,
|
||||
min_8bit,
|
||||
# Meta-parameters
|
||||
BLOCK: tl.constexpr,
|
||||
):
|
||||
"""A Triton-accelerated function to perform per-token-group quantization on a
|
||||
tensor.
|
||||
|
||||
This function converts the tensor values into float8 values.
|
||||
This function converts the tensor values into 8bit values.
|
||||
"""
|
||||
# Map the program id to the row of X and Y it should compute.
|
||||
g_id = tl.program_id(0)
|
||||
@@ -48,30 +47,27 @@ def _per_token_group_quant_fp8(
|
||||
y = tl.load(y_ptr + cols, mask=mask, other=0.0).to(tl.float32)
|
||||
# Quant
|
||||
_absmax = tl.maximum(tl.max(tl.abs(y)), eps)
|
||||
y_s = _absmax / fp8_max
|
||||
y_q = tl.clamp(y / y_s, fp8_min, fp8_max).to(y_q_ptr.dtype.element_ty)
|
||||
y_s = _absmax / max_8bit
|
||||
y_q = tl.clamp(y / y_s, min_8bit, max_8bit).to(y_q_ptr.dtype.element_ty)
|
||||
|
||||
tl.store(y_q_ptr + cols, y_q, mask=mask)
|
||||
tl.store(y_s_ptr, y_s)
|
||||
|
||||
|
||||
def triton_per_token_group_quant_fp8(
|
||||
def triton_per_token_group_quant_8bit(
|
||||
x: torch.Tensor,
|
||||
group_size: int,
|
||||
dst_dtype: torch.dtype,
|
||||
eps: float = 1e-10,
|
||||
dtype: torch.dtype = fp8_type_,
|
||||
) -> Tuple[torch.Tensor, torch.Tensor]:
|
||||
"""Function to perform per-token-group quantization on an input tensor `x`.
|
||||
|
||||
It converts the tensor values into signed float8 values and returns the
|
||||
quantized tensor along with the scaling factor used for quantization.
|
||||
|
||||
Args:
|
||||
x: The input tenosr with ndim >= 2.
|
||||
group_size: The group size used for quantization.
|
||||
eps: The minimum to avoid dividing zero.
|
||||
dtype: The dype of output tensor. Note that only `torch.float8_e4m3fn` is supported for now.
|
||||
|
||||
Returns:
|
||||
Tuple[torch.Tensor, torch.Tensor]: The quantized tensor and the scaling factor for quantization.
|
||||
"""
|
||||
@@ -80,12 +76,16 @@ def triton_per_token_group_quant_fp8(
|
||||
), "the last dimension of `x` cannot be divisible by `group_size`"
|
||||
assert x.is_contiguous(), "`x` is not contiguous"
|
||||
|
||||
finfo = torch.finfo(dtype)
|
||||
fp8_max = finfo.max
|
||||
if dst_dtype == torch.int8:
|
||||
iinfo = torch.iinfo(dst_dtype)
|
||||
max_8bit = iinfo.max
|
||||
min_8bit = iinfo.min
|
||||
else:
|
||||
finfo = torch.finfo(dst_dtype)
|
||||
max_8bit = finfo.max
|
||||
min_8bit = finfo.min
|
||||
|
||||
fp8_min = -fp8_max
|
||||
|
||||
x_q = torch.empty_like(x, device=x.device, dtype=dtype)
|
||||
x_q = torch.empty_like(x, device=x.device, dtype=dst_dtype)
|
||||
M = x.numel() // group_size
|
||||
N = group_size
|
||||
x_s = torch.empty(
|
||||
@@ -98,15 +98,15 @@ def triton_per_token_group_quant_fp8(
|
||||
# heuristics for number of warps
|
||||
num_warps = min(max(BLOCK // 256, 1), 8)
|
||||
num_stages = 1
|
||||
_per_token_group_quant_fp8[(M,)](
|
||||
_per_token_group_quant_8bit[(M,)](
|
||||
x,
|
||||
x_q,
|
||||
x_s,
|
||||
group_size,
|
||||
N,
|
||||
eps,
|
||||
fp8_min=fp8_min,
|
||||
fp8_max=fp8_max,
|
||||
max_8bit,
|
||||
min_8bit,
|
||||
BLOCK=BLOCK,
|
||||
num_warps=num_warps,
|
||||
num_stages=num_stages,
|
||||
@@ -115,53 +115,58 @@ def triton_per_token_group_quant_fp8(
|
||||
return x_q, x_s
|
||||
|
||||
|
||||
def sglang_per_token_group_quant_fp8(
|
||||
def sglang_per_token_group_quant_8bit(
|
||||
x: torch.Tensor,
|
||||
group_size: int,
|
||||
dst_dtype: torch.dtype,
|
||||
eps: float = 1e-10,
|
||||
dtype: torch.dtype = fp8_type_,
|
||||
):
|
||||
assert (
|
||||
x.shape[-1] % group_size == 0
|
||||
), "the last dimension of `x` cannot be divisible by `group_size`"
|
||||
assert x.is_contiguous(), "`x` is not contiguous"
|
||||
|
||||
finfo = torch.finfo(dtype)
|
||||
fp8_max = finfo.max
|
||||
|
||||
fp8_min = -fp8_max
|
||||
|
||||
x_q = torch.empty_like(x, device=x.device, dtype=dtype)
|
||||
M = x.numel() // group_size
|
||||
N = group_size
|
||||
x_q = torch.empty_like(x, device=x.device, dtype=dst_dtype)
|
||||
x_s = torch.empty(
|
||||
x.shape[:-1] + (x.shape[-1] // group_size,),
|
||||
device=x.device,
|
||||
dtype=torch.float32,
|
||||
)
|
||||
|
||||
sgl_per_token_group_quant_fp8(x, x_q, x_s, group_size, eps, fp8_min, fp8_max)
|
||||
if dst_dtype == torch.int8:
|
||||
iinfo = torch.iinfo(dst_dtype)
|
||||
int8_max = iinfo.max
|
||||
int8_min = iinfo.min
|
||||
sgl_per_token_group_quant_int8(x, x_q, x_s, group_size, eps, int8_min, int8_max)
|
||||
else:
|
||||
f8_info = torch.finfo(dst_dtype)
|
||||
fp8_max = f8_info.max
|
||||
fp8_min = f8_info.min
|
||||
sgl_per_token_group_quant_fp8(x, x_q, x_s, group_size, eps, fp8_min, fp8_max)
|
||||
|
||||
return x_q, x_s
|
||||
|
||||
|
||||
@pytest.mark.parametrize(
|
||||
"batch_size, seq_len, group_size",
|
||||
"batch_size, seq_len, group_size, dst_dtype",
|
||||
list(
|
||||
itertools.product(
|
||||
[1, 2, 4, 8, 16, 32, 64, 128], # batch_size
|
||||
[64, 128, 256, 512, 1024, 2048], # seq_len
|
||||
[16, 32, 64, 128, 256], # group_size
|
||||
[torch.int8, fp8_type_], # dtype
|
||||
)
|
||||
),
|
||||
)
|
||||
def test_per_token_group_quant_compare_implementations(batch_size, seq_len, group_size):
|
||||
def test_per_token_group_quant_compare_implementations(
|
||||
batch_size, seq_len, group_size, dst_dtype
|
||||
):
|
||||
x = torch.randn(
|
||||
(batch_size, seq_len, group_size * 2), device="cuda", dtype=torch.float16
|
||||
)
|
||||
|
||||
x_q_triton, x_s_triton = triton_per_token_group_quant_fp8(x, group_size)
|
||||
x_q_sglang, x_s_sglang = sglang_per_token_group_quant_fp8(x, group_size)
|
||||
x_q_triton, x_s_triton = triton_per_token_group_quant_8bit(x, group_size, dst_dtype)
|
||||
x_q_sglang, x_s_sglang = sglang_per_token_group_quant_8bit(x, group_size, dst_dtype)
|
||||
|
||||
assert torch.allclose(
|
||||
x_q_triton.to(torch.float32), x_q_sglang.to(torch.float32), rtol=1e-3, atol=1e-5
|
||||
Reference in New Issue
Block a user