517 lines
18 KiB
Python
517 lines
18 KiB
Python
import math
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import sys
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import traceback
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import psutil
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import torch
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from torch import einsum
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from ldm.util import default
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from einops import rearrange
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from modules import shared, errors, devices
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from modules.hypernetworks import hypernetwork
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from .sub_quadratic_attention import efficient_dot_product_attention
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if shared.cmd_opts.xformers or shared.cmd_opts.force_enable_xformers:
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try:
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import xformers.ops
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shared.xformers_available = True
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except Exception:
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print("Cannot import xformers", file=sys.stderr)
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print(traceback.format_exc(), file=sys.stderr)
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def get_available_vram():
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if shared.device.type == 'cuda':
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stats = torch.cuda.memory_stats(shared.device)
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mem_active = stats['active_bytes.all.current']
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mem_reserved = stats['reserved_bytes.all.current']
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mem_free_cuda, _ = torch.cuda.mem_get_info(torch.cuda.current_device())
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mem_free_torch = mem_reserved - mem_active
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mem_free_total = mem_free_cuda + mem_free_torch
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return mem_free_total
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else:
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return psutil.virtual_memory().available
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# see https://github.com/basujindal/stable-diffusion/pull/117 for discussion
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def split_cross_attention_forward_v1(self, x, context=None, mask=None):
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h = self.heads
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q_in = self.to_q(x)
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context = default(context, x)
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context_k, context_v = hypernetwork.apply_hypernetworks(shared.loaded_hypernetworks, context)
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k_in = self.to_k(context_k)
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v_in = self.to_v(context_v)
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del context, context_k, context_v, x
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q, k, v = (rearrange(t, 'b n (h d) -> (b h) n d', h=h) for t in (q_in, k_in, v_in))
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del q_in, k_in, v_in
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dtype = q.dtype
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if shared.opts.upcast_attn:
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q, k, v = q.float(), k.float(), v.float()
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with devices.without_autocast(disable=not shared.opts.upcast_attn):
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r1 = torch.zeros(q.shape[0], q.shape[1], v.shape[2], device=q.device, dtype=q.dtype)
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for i in range(0, q.shape[0], 2):
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end = i + 2
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s1 = einsum('b i d, b j d -> b i j', q[i:end], k[i:end])
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s1 *= self.scale
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s2 = s1.softmax(dim=-1)
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del s1
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r1[i:end] = einsum('b i j, b j d -> b i d', s2, v[i:end])
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del s2
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del q, k, v
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r1 = r1.to(dtype)
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r2 = rearrange(r1, '(b h) n d -> b n (h d)', h=h)
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del r1
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return self.to_out(r2)
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# taken from https://github.com/Doggettx/stable-diffusion and modified
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def split_cross_attention_forward(self, x, context=None, mask=None):
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h = self.heads
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q_in = self.to_q(x)
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context = default(context, x)
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context_k, context_v = hypernetwork.apply_hypernetworks(shared.loaded_hypernetworks, context)
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k_in = self.to_k(context_k)
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v_in = self.to_v(context_v)
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dtype = q_in.dtype
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if shared.opts.upcast_attn:
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q_in, k_in, v_in = q_in.float(), k_in.float(), v_in if v_in.device.type == 'mps' else v_in.float()
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with devices.without_autocast(disable=not shared.opts.upcast_attn):
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k_in = k_in * self.scale
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del context, x
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q, k, v = (rearrange(t, 'b n (h d) -> (b h) n d', h=h) for t in (q_in, k_in, v_in))
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del q_in, k_in, v_in
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r1 = torch.zeros(q.shape[0], q.shape[1], v.shape[2], device=q.device, dtype=q.dtype)
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mem_free_total = get_available_vram()
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gb = 1024 ** 3
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tensor_size = q.shape[0] * q.shape[1] * k.shape[1] * q.element_size()
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modifier = 3 if q.element_size() == 2 else 2.5
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mem_required = tensor_size * modifier
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steps = 1
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if mem_required > mem_free_total:
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steps = 2 ** (math.ceil(math.log(mem_required / mem_free_total, 2)))
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# print(f"Expected tensor size:{tensor_size/gb:0.1f}GB, cuda free:{mem_free_cuda/gb:0.1f}GB "
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# f"torch free:{mem_free_torch/gb:0.1f} total:{mem_free_total/gb:0.1f} steps:{steps}")
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if steps > 64:
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max_res = math.floor(math.sqrt(math.sqrt(mem_free_total / 2.5)) / 8) * 64
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raise RuntimeError(f'Not enough memory, use lower resolution (max approx. {max_res}x{max_res}). '
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f'Need: {mem_required / 64 / gb:0.1f}GB free, Have:{mem_free_total / gb:0.1f}GB free')
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slice_size = q.shape[1] // steps if (q.shape[1] % steps) == 0 else q.shape[1]
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for i in range(0, q.shape[1], slice_size):
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end = i + slice_size
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s1 = einsum('b i d, b j d -> b i j', q[:, i:end], k)
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s2 = s1.softmax(dim=-1, dtype=q.dtype)
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del s1
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r1[:, i:end] = einsum('b i j, b j d -> b i d', s2, v)
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del s2
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del q, k, v
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r1 = r1.to(dtype)
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r2 = rearrange(r1, '(b h) n d -> b n (h d)', h=h)
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del r1
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return self.to_out(r2)
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# -- Taken from https://github.com/invoke-ai/InvokeAI and modified --
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mem_total_gb = psutil.virtual_memory().total // (1 << 30)
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def einsum_op_compvis(q, k, v):
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s = einsum('b i d, b j d -> b i j', q, k)
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s = s.softmax(dim=-1, dtype=s.dtype)
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return einsum('b i j, b j d -> b i d', s, v)
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def einsum_op_slice_0(q, k, v, slice_size):
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r = torch.zeros(q.shape[0], q.shape[1], v.shape[2], device=q.device, dtype=q.dtype)
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for i in range(0, q.shape[0], slice_size):
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end = i + slice_size
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r[i:end] = einsum_op_compvis(q[i:end], k[i:end], v[i:end])
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return r
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def einsum_op_slice_1(q, k, v, slice_size):
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r = torch.zeros(q.shape[0], q.shape[1], v.shape[2], device=q.device, dtype=q.dtype)
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for i in range(0, q.shape[1], slice_size):
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end = i + slice_size
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r[:, i:end] = einsum_op_compvis(q[:, i:end], k, v)
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return r
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def einsum_op_mps_v1(q, k, v):
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if q.shape[0] * q.shape[1] <= 2**16: # (512x512) max q.shape[1]: 4096
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return einsum_op_compvis(q, k, v)
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else:
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slice_size = math.floor(2**30 / (q.shape[0] * q.shape[1]))
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if slice_size % 4096 == 0:
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slice_size -= 1
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return einsum_op_slice_1(q, k, v, slice_size)
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def einsum_op_mps_v2(q, k, v):
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if mem_total_gb > 8 and q.shape[0] * q.shape[1] <= 2**16:
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return einsum_op_compvis(q, k, v)
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else:
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return einsum_op_slice_0(q, k, v, 1)
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def einsum_op_tensor_mem(q, k, v, max_tensor_mb):
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size_mb = q.shape[0] * q.shape[1] * k.shape[1] * q.element_size() // (1 << 20)
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if size_mb <= max_tensor_mb:
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return einsum_op_compvis(q, k, v)
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div = 1 << int((size_mb - 1) / max_tensor_mb).bit_length()
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if div <= q.shape[0]:
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return einsum_op_slice_0(q, k, v, q.shape[0] // div)
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return einsum_op_slice_1(q, k, v, max(q.shape[1] // div, 1))
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def einsum_op_cuda(q, k, v):
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stats = torch.cuda.memory_stats(q.device)
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mem_active = stats['active_bytes.all.current']
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mem_reserved = stats['reserved_bytes.all.current']
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mem_free_cuda, _ = torch.cuda.mem_get_info(q.device)
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mem_free_torch = mem_reserved - mem_active
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mem_free_total = mem_free_cuda + mem_free_torch
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# Divide factor of safety as there's copying and fragmentation
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return einsum_op_tensor_mem(q, k, v, mem_free_total / 3.3 / (1 << 20))
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def einsum_op(q, k, v):
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if q.device.type == 'cuda':
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return einsum_op_cuda(q, k, v)
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if q.device.type == 'mps':
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if mem_total_gb >= 32 and q.shape[0] % 32 != 0 and q.shape[0] * q.shape[1] < 2**18:
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return einsum_op_mps_v1(q, k, v)
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return einsum_op_mps_v2(q, k, v)
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# Smaller slices are faster due to L2/L3/SLC caches.
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# Tested on i7 with 8MB L3 cache.
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return einsum_op_tensor_mem(q, k, v, 32)
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def split_cross_attention_forward_invokeAI(self, x, context=None, mask=None):
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h = self.heads
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q = self.to_q(x)
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context = default(context, x)
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context_k, context_v = hypernetwork.apply_hypernetworks(shared.loaded_hypernetworks, context)
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k = self.to_k(context_k)
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v = self.to_v(context_v)
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del context, context_k, context_v, x
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dtype = q.dtype
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if shared.opts.upcast_attn:
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q, k, v = q.float(), k.float(), v if v.device.type == 'mps' else v.float()
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with devices.without_autocast(disable=not shared.opts.upcast_attn):
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k = k * self.scale
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q, k, v = (rearrange(t, 'b n (h d) -> (b h) n d', h=h) for t in (q, k, v))
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r = einsum_op(q, k, v)
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r = r.to(dtype)
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return self.to_out(rearrange(r, '(b h) n d -> b n (h d)', h=h))
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# -- End of code from https://github.com/invoke-ai/InvokeAI --
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# Based on Birch-san's modified implementation of sub-quadratic attention from https://github.com/Birch-san/diffusers/pull/1
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# The sub_quad_attention_forward function is under the MIT License listed under Memory Efficient Attention in the Licenses section of the web UI interface
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def sub_quad_attention_forward(self, x, context=None, mask=None):
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assert mask is None, "attention-mask not currently implemented for SubQuadraticCrossAttnProcessor."
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h = self.heads
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q = self.to_q(x)
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context = default(context, x)
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context_k, context_v = hypernetwork.apply_hypernetworks(shared.loaded_hypernetworks, context)
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k = self.to_k(context_k)
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v = self.to_v(context_v)
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del context, context_k, context_v, x
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q = q.unflatten(-1, (h, -1)).transpose(1,2).flatten(end_dim=1)
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k = k.unflatten(-1, (h, -1)).transpose(1,2).flatten(end_dim=1)
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v = v.unflatten(-1, (h, -1)).transpose(1,2).flatten(end_dim=1)
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if q.device.type == 'mps':
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q, k, v = q.contiguous(), k.contiguous(), v.contiguous()
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dtype = q.dtype
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if shared.opts.upcast_attn:
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q, k = q.float(), k.float()
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x = sub_quad_attention(q, k, v, q_chunk_size=shared.cmd_opts.sub_quad_q_chunk_size, kv_chunk_size=shared.cmd_opts.sub_quad_kv_chunk_size, chunk_threshold=shared.cmd_opts.sub_quad_chunk_threshold, use_checkpoint=self.training)
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x = x.to(dtype)
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x = x.unflatten(0, (-1, h)).transpose(1,2).flatten(start_dim=2)
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out_proj, dropout = self.to_out
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x = out_proj(x)
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x = dropout(x)
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return x
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def sub_quad_attention(q, k, v, q_chunk_size=1024, kv_chunk_size=None, kv_chunk_size_min=None, chunk_threshold=None, use_checkpoint=True):
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bytes_per_token = torch.finfo(q.dtype).bits//8
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batch_x_heads, q_tokens, _ = q.shape
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_, k_tokens, _ = k.shape
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qk_matmul_size_bytes = batch_x_heads * bytes_per_token * q_tokens * k_tokens
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if chunk_threshold is None:
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chunk_threshold_bytes = int(get_available_vram() * 0.9) if q.device.type == 'mps' else int(get_available_vram() * 0.7)
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elif chunk_threshold == 0:
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chunk_threshold_bytes = None
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else:
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chunk_threshold_bytes = int(0.01 * chunk_threshold * get_available_vram())
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if kv_chunk_size_min is None and chunk_threshold_bytes is not None:
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kv_chunk_size_min = chunk_threshold_bytes // (batch_x_heads * bytes_per_token * (k.shape[2] + v.shape[2]))
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elif kv_chunk_size_min == 0:
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kv_chunk_size_min = None
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if chunk_threshold_bytes is not None and qk_matmul_size_bytes <= chunk_threshold_bytes:
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# the big matmul fits into our memory limit; do everything in 1 chunk,
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# i.e. send it down the unchunked fast-path
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kv_chunk_size = k_tokens
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with devices.without_autocast(disable=q.dtype == v.dtype):
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return efficient_dot_product_attention(
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q,
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k,
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v,
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query_chunk_size=q_chunk_size,
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kv_chunk_size=kv_chunk_size,
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kv_chunk_size_min = kv_chunk_size_min,
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use_checkpoint=use_checkpoint,
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)
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def get_xformers_flash_attention_op(q, k, v):
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if not shared.cmd_opts.xformers_flash_attention:
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return None
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try:
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flash_attention_op = xformers.ops.MemoryEfficientAttentionFlashAttentionOp
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fw, bw = flash_attention_op
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if fw.supports(xformers.ops.fmha.Inputs(query=q, key=k, value=v, attn_bias=None)):
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return flash_attention_op
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except Exception as e:
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errors.display_once(e, "enabling flash attention")
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return None
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def xformers_attention_forward(self, x, context=None, mask=None):
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h = self.heads
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q_in = self.to_q(x)
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context = default(context, x)
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context_k, context_v = hypernetwork.apply_hypernetworks(shared.loaded_hypernetworks, context)
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k_in = self.to_k(context_k)
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v_in = self.to_v(context_v)
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q, k, v = (rearrange(t, 'b n (h d) -> b n h d', h=h) for t in (q_in, k_in, v_in))
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del q_in, k_in, v_in
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dtype = q.dtype
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if shared.opts.upcast_attn:
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q, k, v = q.float(), k.float(), v.float()
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out = xformers.ops.memory_efficient_attention(q, k, v, attn_bias=None, op=get_xformers_flash_attention_op(q, k, v))
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out = out.to(dtype)
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out = rearrange(out, 'b n h d -> b n (h d)', h=h)
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return self.to_out(out)
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# Based on Diffusers usage of scaled dot product attention from https://github.com/huggingface/diffusers/blob/c7da8fd23359a22d0df2741688b5b4f33c26df21/src/diffusers/models/cross_attention.py
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# The scaled_dot_product_attention_forward function contains parts of code under Apache-2.0 license listed under Scaled Dot Product Attention in the Licenses section of the web UI interface
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def scaled_dot_product_attention_forward(self, x, context=None, mask=None):
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batch_size, sequence_length, inner_dim = x.shape
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if mask is not None:
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mask = self.prepare_attention_mask(mask, sequence_length, batch_size)
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mask = mask.view(batch_size, self.heads, -1, mask.shape[-1])
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h = self.heads
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q_in = self.to_q(x)
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context = default(context, x)
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context_k, context_v = hypernetwork.apply_hypernetworks(shared.loaded_hypernetworks, context)
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k_in = self.to_k(context_k)
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v_in = self.to_v(context_v)
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head_dim = inner_dim // h
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q = q_in.view(batch_size, -1, h, head_dim).transpose(1, 2)
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k = k_in.view(batch_size, -1, h, head_dim).transpose(1, 2)
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v = v_in.view(batch_size, -1, h, head_dim).transpose(1, 2)
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del q_in, k_in, v_in
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dtype = q.dtype
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if shared.opts.upcast_attn:
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q, k, v = q.float(), k.float(), v.float()
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# the output of sdp = (batch, num_heads, seq_len, head_dim)
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hidden_states = torch.nn.functional.scaled_dot_product_attention(
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q, k, v, attn_mask=mask, dropout_p=0.0, is_causal=False
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)
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hidden_states = hidden_states.transpose(1, 2).reshape(batch_size, -1, h * head_dim)
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hidden_states = hidden_states.to(dtype)
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# linear proj
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hidden_states = self.to_out[0](hidden_states)
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# dropout
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hidden_states = self.to_out[1](hidden_states)
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return hidden_states
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def scaled_dot_product_no_mem_attention_forward(self, x, context=None, mask=None):
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with torch.backends.cuda.sdp_kernel(enable_flash=True, enable_math=True, enable_mem_efficient=False):
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return scaled_dot_product_attention_forward(self, x, context, mask)
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def cross_attention_attnblock_forward(self, x):
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h_ = x
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h_ = self.norm(h_)
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q1 = self.q(h_)
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k1 = self.k(h_)
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v = self.v(h_)
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# compute attention
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b, c, h, w = q1.shape
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q2 = q1.reshape(b, c, h*w)
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del q1
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q = q2.permute(0, 2, 1) # b,hw,c
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del q2
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k = k1.reshape(b, c, h*w) # b,c,hw
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del k1
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h_ = torch.zeros_like(k, device=q.device)
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mem_free_total = get_available_vram()
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tensor_size = q.shape[0] * q.shape[1] * k.shape[2] * q.element_size()
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mem_required = tensor_size * 2.5
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steps = 1
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if mem_required > mem_free_total:
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steps = 2**(math.ceil(math.log(mem_required / mem_free_total, 2)))
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slice_size = q.shape[1] // steps if (q.shape[1] % steps) == 0 else q.shape[1]
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for i in range(0, q.shape[1], slice_size):
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end = i + slice_size
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w1 = torch.bmm(q[:, i:end], k) # b,hw,hw w[b,i,j]=sum_c q[b,i,c]k[b,c,j]
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w2 = w1 * (int(c)**(-0.5))
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del w1
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w3 = torch.nn.functional.softmax(w2, dim=2, dtype=q.dtype)
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del w2
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|
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# attend to values
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v1 = v.reshape(b, c, h*w)
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w4 = w3.permute(0, 2, 1) # b,hw,hw (first hw of k, second of q)
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|
del w3
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|
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h_[:, :, i:end] = torch.bmm(v1, w4) # b, c,hw (hw of q) h_[b,c,j] = sum_i v[b,c,i] w_[b,i,j]
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|
del v1, w4
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|
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|
h2 = h_.reshape(b, c, h, w)
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|
del h_
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|
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|
h3 = self.proj_out(h2)
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|
del h2
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|
|
|
h3 += x
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|
|
|
return h3
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|
|
|
def xformers_attnblock_forward(self, x):
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|
try:
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|
h_ = x
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|
h_ = self.norm(h_)
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|
q = self.q(h_)
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|
k = self.k(h_)
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|
v = self.v(h_)
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|
b, c, h, w = q.shape
|
|
q, k, v = (rearrange(t, 'b c h w -> b (h w) c') for t in (q, k, v))
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|
dtype = q.dtype
|
|
if shared.opts.upcast_attn:
|
|
q, k = q.float(), k.float()
|
|
q = q.contiguous()
|
|
k = k.contiguous()
|
|
v = v.contiguous()
|
|
out = xformers.ops.memory_efficient_attention(q, k, v, op=get_xformers_flash_attention_op(q, k, v))
|
|
out = out.to(dtype)
|
|
out = rearrange(out, 'b (h w) c -> b c h w', h=h)
|
|
out = self.proj_out(out)
|
|
return x + out
|
|
except NotImplementedError:
|
|
return cross_attention_attnblock_forward(self, x)
|
|
|
|
def sdp_attnblock_forward(self, x):
|
|
h_ = x
|
|
h_ = self.norm(h_)
|
|
q = self.q(h_)
|
|
k = self.k(h_)
|
|
v = self.v(h_)
|
|
b, c, h, w = q.shape
|
|
q, k, v = (rearrange(t, 'b c h w -> b (h w) c') for t in (q, k, v))
|
|
dtype = q.dtype
|
|
if shared.opts.upcast_attn:
|
|
q, k = q.float(), k.float()
|
|
q = q.contiguous()
|
|
k = k.contiguous()
|
|
v = v.contiguous()
|
|
out = torch.nn.functional.scaled_dot_product_attention(q, k, v, dropout_p=0.0, is_causal=False)
|
|
out = out.to(dtype)
|
|
out = rearrange(out, 'b (h w) c -> b c h w', h=h)
|
|
out = self.proj_out(out)
|
|
return x + out
|
|
|
|
def sdp_no_mem_attnblock_forward(self, x):
|
|
with torch.backends.cuda.sdp_kernel(enable_flash=True, enable_math=True, enable_mem_efficient=False):
|
|
return sdp_attnblock_forward(self, x)
|
|
|
|
def sub_quad_attnblock_forward(self, x):
|
|
h_ = x
|
|
h_ = self.norm(h_)
|
|
q = self.q(h_)
|
|
k = self.k(h_)
|
|
v = self.v(h_)
|
|
b, c, h, w = q.shape
|
|
q, k, v = (rearrange(t, 'b c h w -> b (h w) c') for t in (q, k, v))
|
|
q = q.contiguous()
|
|
k = k.contiguous()
|
|
v = v.contiguous()
|
|
out = sub_quad_attention(q, k, v, q_chunk_size=shared.cmd_opts.sub_quad_q_chunk_size, kv_chunk_size=shared.cmd_opts.sub_quad_kv_chunk_size, chunk_threshold=shared.cmd_opts.sub_quad_chunk_threshold, use_checkpoint=self.training)
|
|
out = rearrange(out, 'b (h w) c -> b c h w', h=h)
|
|
out = self.proj_out(out)
|
|
return x + out
|