Spaces:
Running
on
Zero
Running
on
Zero
import torch | |
from typing import Tuple | |
from rotary import RotaryEmbedding | |
import time | |
def precompute_freqs_cis(dim: int, end: int, theta: float = 10000.0): | |
freqs = 1.0 / (theta ** (torch.arange(0, dim, 2)[: (dim // 2)].float() / dim)) | |
t = torch.arange(end, device=freqs.device, dtype=torch.float32) | |
freqs = torch.outer(t, freqs) | |
freqs_cis = torch.polar(torch.ones_like(freqs), freqs) # complex64 | |
return freqs_cis | |
def reshape_for_broadcast(freqs_cis: torch.Tensor, | |
x: torch.Tensor,): | |
ndim = x.ndim | |
assert 0 <= 1 < ndim | |
assert freqs_cis.shape == (x.shape[1], x.shape[-1]) | |
shape = [d if i == 1 or i == ndim - 1 else 1 for i, d in enumerate(x.shape)] | |
return freqs_cis.view(*shape) | |
def compute_rope(q, freqs_cis): | |
return q * freqs_cis | |
def apply_rotary_emb( | |
xq: torch.Tensor, | |
xk: torch.Tensor, | |
freqs_cis: torch.Tensor, | |
) -> Tuple[torch.Tensor, torch.Tensor]: | |
# xq_ = torch.view_as_complex(xq.float().reshape(*xq.shape[:-1], -1, 2)) | |
# xk_ = torch.view_as_complex(xk.float().reshape(*xk.shape[:-1], -1, 2)) | |
xq1, xq2 = xq.chunk(2, dim=-1) | |
xq_ = torch.view_as_complex(torch.stack((xq1, xq2), dim=-1).float()) | |
xk1, xk2 = xk.chunk(2, dim=-1) | |
xk_ = torch.view_as_complex(torch.stack((xk1, xk2), dim=-1).float()) | |
freqs_cis = reshape_for_broadcast(freqs_cis, xq_) | |
xq_out = torch.view_as_real(compute_rope(xq_, freqs_cis)).flatten(3) | |
xk_out = torch.view_as_real(compute_rope(xk_, freqs_cis)).flatten(3) | |
return xq_out.type_as(xq), xk_out.type_as(xk) | |
if __name__ == '__main__': | |
# Move data to CUDA | |
freq_cis = precompute_freqs_cis(4, 5).cuda() | |
x = torch.rand(1, 5, 1, 4).cuda() | |
y = torch.rand(1, 5, 1, 4).cuda() | |
# First method | |
start_time = time.time() | |
for _ in range(20000): | |
x1, y1 = apply_rotary_emb(x, y, freq_cis) | |
end_time = time.time() | |
print(f"Method 1 time cost: {end_time - start_time} seconds") | |
# Prepare data for the second method | |
x = x.permute(0, 2, 1, 3) | |
y = y.permute(0, 2, 1, 3) | |
rope = RotaryEmbedding(4).cuda() | |
# Second method | |
start_time = time.time() | |
for _ in range(20000): | |
x2, y2 = rope(x, y) | |
end_time = time.time() | |
print(f"Method 2 time cost: {end_time - start_time} seconds") | |
# Print the results | |
print(x1) | |
print(x2) |