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init support for MLA using Attention kernel

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Atream 2025-02-13 15:01:14 +00:00
parent 62011fd63e
commit bb35dc5b0d
5 changed files with 551 additions and 262 deletions
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45
ktransformers/models/custom_cache.py
View file

@ -51,13 +51,33 @@ class StaticCache(transformers.StaticCache):
cache_shape = (max_batch_size, self.num_key_value_heads, self.max_cache_len, self.head_dim)
if config.architectures[0] == "DeepseekV2ForCausalLM" or config.architectures[0] == "DeepseekV3ForCausalLM":
# TODO: for deepseek, cache_shape is different whether using Absorbed MLA, check it automatically
# key_shape = (max_batch_size, self.num_key_value_heads, self.max_cache_len, config.qk_rope_head_dim + config.qk_nope_head_dim)
# value_shape = (max_batch_size, self.num_key_value_heads, self.max_cache_len, config.v_head_dim)
key_shape = (max_batch_size, 1, self.max_cache_len, config.qk_rope_head_dim)
value_shape = (max_batch_size, 1, self.max_cache_len, config.kv_lora_rank)
self.page_size = 64
self.max_pages = (self.max_cache_len + self.page_size - 1) // self.page_size
key_shape = (self.max_pages, self.page_size, 1, config.qk_rope_head_dim)
value_shape = (self.max_pages, self.page_size, 1, config.kv_lora_rank)
# TODO: support real page table
self.page_table_map = dict()
self.page_table_list = []
for idx in range(config.num_hidden_layers):
if isinstance(device, dict):
target_device = device[f"blk.{idx}.self_attn"]["generate_device"]
else:
target_device = device
if target_device not in self.page_table_map:
page_table = torch.zeros((max_batch_size, self.max_pages), dtype=torch.int32, device=target_device)
for seq_id in range(max_batch_size):
page_table[seq_id, :] = torch.arange(seq_id * self.max_pages, seq_id * self.max_pages + self.max_pages, dtype=torch.int32, device=target_device)
self.page_table_map[target_device] = page_table
self.page_table_list.append(self.page_table_map[target_device])
self.is_MLA = True
self.is_page = True
else:
key_shape = cache_shape
value_shape = cache_shape
self.is_MLA = False
self.past_tokens = []
self.num_hidden_layers = config.num_hidden_layers
@ -104,11 +124,20 @@ class StaticCache(transformers.StaticCache):
cache_position = cache_kwargs.get("cache_position")
k_out = self.key_cache[layer_idx]
v_out = self.value_cache[layer_idx]
#print(cache_position)
k_out[:, :, cache_position] = key_states
v_out[:, :, cache_position] = value_states
self.past_tokens[layer_idx] += cache_position.size(0)
return k_out, v_out
#print(cache_position)
if self.is_MLA:
page_idx = cache_position // self.page_size
page_offset = cache_position % self.page_size
#print("page_idx", page_idx)
#print("page_offset", page_offset)
k_out[page_idx, page_offset, ...] = key_states
v_out[page_idx, page_offset, ...] = value_states
return k_out, v_out, self.page_table_list[layer_idx]
else:
k_out[:, :, cache_position] = key_states
v_out[:, :, cache_position] = value_states
return k_out, v_out
def get_seq_length(self, layer_idx: Optional[int] = 0) -> int:
"""Returns the sequence length of the cached states that were seen by the model."""

376
ktransformers/operators/attention.py
View file

@ -21,207 +21,12 @@ from ktransformers.util.custom_gguf import GGUFLoader
import logging
from transformers.configuration_utils import PretrainedConfig
from transformers.cache_utils import Cache
from flash_attn import flash_attn_with_kvcache, flash_attn_func
from ktransformers.operators.triton_attention import decode_attention_fwd_grouped
logger = logging.getLogger("attention")
class KDeepseekV3Attention(BaseInjectedModule, DeepseekV3Attention):
"""Multi-headed attention from 'Attention Is All You Need' paper"""
attn_mask: Optional[torch.Tensor] = None
def __init__(self,
key: str,
gguf_loader : GGUFLoader,
config: PretrainedConfig,
orig_module: nn.Module,
device: str = "cuda",
chunck_size: int = 1000,
**kwargs):
BaseInjectedModule.__init__(self, key, gguf_loader, config, orig_module, device, **kwargs)
self.orig_module.__init__(orig_module.config,
orig_module.layer_idx)
self.chunck_size = chunck_size # TODO, generate chunck_size automatically.
self.softmax_scale = self.q_head_dim ** (-0.5)
def get_absorbed(self) -> Tuple[torch.Tensor, torch.Tensor]:
if not (hasattr(self, 'q_absorb') and hasattr(self, 'out_absorb')):
kv_b_proj = self.kv_b_proj.weight.view(self.num_heads, -1, self.kv_lora_rank)
q_absorb = kv_b_proj[:, :self.qk_nope_head_dim, :].reshape(-1, self.kv_lora_rank)
out_absorb = kv_b_proj[:, self.qk_nope_head_dim:, :].reshape(-1, self.kv_lora_rank)
self.q_absorb = nn.Linear(self.kv_lora_rank, self.num_heads * self.qk_nope_head_dim,
bias=False, dtype=q_absorb.dtype, device=q_absorb.device)
self.q_absorb.weight.data = q_absorb
self.out_absorb = nn.Linear(self.kv_lora_rank, self.num_heads * self.v_head_dim,
bias=False, dtype=out_absorb.dtype, device=out_absorb.device)
self.out_absorb.weight.data = out_absorb
del self.orig_module.kv_b_proj
q_absorb = self.q_absorb.weight.view(self.num_heads, self.qk_nope_head_dim, self.kv_lora_rank)
out_absorb = self.out_absorb.weight.view(self.num_heads, self.v_head_dim, self.kv_lora_rank)
return q_absorb, out_absorb
def forward_chunck(
self,
hidden_states: torch.Tensor,
attention_mask: Optional[torch.Tensor] = None,
position_ids: Optional[torch.LongTensor] = None,
past_key_value: Optional[Cache] = None,
output_attentions: bool = False,
use_cache: bool = False,
cache_position: Optional[torch.LongTensor] = None,
**kwargs
) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]:
bsz, q_len, _ = hidden_states.size()
if self.q_lora_rank is None:
q = self.q_proj(hidden_states)
else:
q = self.q_b_proj(self.q_a_layernorm(self.q_a_proj(hidden_states)))
q = q.view(bsz, q_len, self.num_heads, self.q_head_dim).transpose(1, 2)
q_nope, q_pe = torch.split(
q, [self.qk_nope_head_dim, self.qk_rope_head_dim], dim=-1
)
compressed_kv = self.kv_a_proj_with_mqa(hidden_states)
compressed_kv, k_pe = torch.split(
compressed_kv, [self.kv_lora_rank, self.qk_rope_head_dim], dim=-1
)
compressed_kv = self.kv_a_layernorm(compressed_kv)
k_pe = k_pe.view(bsz, q_len, 1, self.qk_rope_head_dim).transpose(1, 2)
kv_seq_len = k_pe.shape[-2]
if past_key_value is not None:
if self.layer_idx is None:
raise ValueError(
f"The cache structure has changed since version v4.36. If you are using {self.__class__.__name__} "
"for auto-regressive decoding with k/v caching, please make sure to initialize the attention class "
"with a layer index."
)
kv_seq_len += past_key_value.get_usable_length(kv_seq_len, self.layer_idx)
cos, sin = self.rotary_emb(q_pe, position_ids)
q_pe, k_pe = apply_rotary_pos_emb_v3(q_pe, k_pe, cos, sin)
if past_key_value is not None:
cache_kwargs = {"sin": sin, "cos": cos, "cache_position": cache_position} # Specific to RoPE models
compressed_kv = compressed_kv.unsqueeze(1)
k_pe, compressed_kv = past_key_value.update(k_pe, compressed_kv, self.layer_idx, cache_kwargs)
compressed_kv = compressed_kv.squeeze(1)
#if cache_position is not None:
# compressed_kv = compressed_kv[:,: cache_position[-1] + 1,:]
# k_pe = k_pe[:,:,: cache_position[-1] + 1,:]
q_absorb, out_absorb = self.get_absorbed()
q_nope = torch.matmul(q_nope, q_absorb)
attn_weights = (torch.matmul(q_pe, k_pe.mT) + torch.matmul(q_nope, compressed_kv.unsqueeze(-3).mT)) * self.softmax_scale
"""
if attn_weights.size() != (bsz, self.num_heads, q_len, kv_seq_len):
raise ValueError(
f"Attention weights should be of size {(bsz, self.num_heads, q_len, kv_seq_len)}, but is"
f" {attn_weights.size()}"
)
assert attention_mask is not None
"""
if attention_mask is not None:
"""
if attention_mask.size() != (bsz, 1, q_len, kv_seq_len):
raise ValueError(
f"Attention mask should be of size {(bsz, 1, q_len, kv_seq_len)}, but is {attention_mask.size()}"
)
"""
#causal_mask = attention_mask[:, :, :, : kv_seq_len]
attn_weights = attn_weights + attention_mask
# upcast attention to fp32
attn_weights = nn.functional.softmax(
attn_weights, dim=-1, dtype=torch.float32
).to(q_pe.dtype)
attn_weights = nn.functional.dropout(
attn_weights, p=self.attention_dropout, training=self.training
)
attn_output = torch.einsum('bhql,blc->bhqc', attn_weights, compressed_kv)
attn_output = torch.matmul(attn_output, out_absorb.mT)
if attn_output.size() != (bsz, self.num_heads, q_len, self.v_head_dim):
raise ValueError(
f"`attn_output` should be of size {(bsz, self.num_heads, q_len, self.v_head_dim)}, but is"
f" {attn_output.size()}"
)
attn_output = attn_output.transpose(1, 2).contiguous()
attn_output = attn_output.reshape(bsz, q_len, self.num_heads * self.v_head_dim)
attn_output = self.o_proj(attn_output)
return attn_output, attn_weights, past_key_value
def forward(
self,
hidden_states: torch.Tensor,
attention_mask: Optional[torch.Tensor] = None,
position_ids: Optional[torch.LongTensor] = None,
past_key_value: Optional[Cache] = None,
output_attentions: bool = False,
use_cache: bool = False,
cache_position: Optional[torch.LongTensor] = None,
**kwargs,
) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]:
if "padding_mask" in kwargs:
warnings.warn(
"Passing `padding_mask` is deprecated and will be removed in v4.37. Please make sure use `attention_mask` instead.`"
)
bsz, q_len, _ = hidden_states.size()
if q_len <= self.chunck_size:
return self.forward_chunck(
hidden_states,
attention_mask,
position_ids,
past_key_value,
output_attentions,
use_cache,
cache_position,
**kwargs
)
assert output_attentions == False, "output_attentions is not supported when using chunked attention"
attn_output = None
attn_weight = None
cur_idx = 0
while cur_idx < q_len:
if attention_mask is not None:
chunk_mask = attention_mask[:, :, cur_idx:min(cur_idx + self.chunck_size, q_len), ...]
else:
# generate chunk_mask automatically.
self.attn_mask = \
torch.zeros(1, 1, self.chunck_size, past_key_value.max_cache_len, device=hidden_states.device) \
if self.attn_mask is None \
else self.attn_mask
self.attn_mask[:, :, :, cur_idx:min(cur_idx+self.chunck_size, past_key_value.max_cache_len)] = \
-1e+38 * torch.triu(torch.ones(self.chunck_size, self.chunck_size, device=hidden_states.device), diagonal=1)\
[:,:min(self.chunck_size, min(past_key_value.max_cache_len-cur_idx, self.chunck_size))]
self.attn_mask[:, :, :, cur_idx+self.chunck_size:] = -1e+38
self.attn_mask[:, :, :, :cur_idx] = 0
chunk_mask = torch.narrow(self.attn_mask, 2, 0, min(self.chunck_size, q_len-cur_idx))
cur_output, cur_attn_weight = self.forward_chunck(
hidden_states[:, cur_idx:min(cur_idx + self.chunck_size, q_len), ...],
chunk_mask,
position_ids[:, cur_idx:min(cur_idx + self.chunck_size, q_len)],
past_key_value,
output_attentions,
use_cache,
cache_position[cur_idx:min(cur_idx + self.chunck_size, q_len)],
**kwargs
)
cur_idx += self.chunck_size
if attn_output is None:
attn_output = cur_output
attn_weight = cur_attn_weight
else:
attn_output = torch.cat((attn_output, cur_output), dim=-2)
attn_weight = torch.cat((attn_weight, cur_attn_weight), dim=-2)
return attn_output, attn_weight, past_key_value
# V3 MLA is same to V2
class KDeepseekV2Attention(BaseInjectedModule, DeepseekV2Attention):
"""Multi-headed attention from 'Attention Is All You Need' paper"""
attn_mask: Optional[torch.Tensor] = None
@ -250,7 +55,7 @@ class KDeepseekV2Attention(BaseInjectedModule, DeepseekV2Attention):
self.out_absorb = nn.Linear(self.kv_lora_rank, self.num_heads * self.v_head_dim,
bias=False, dtype=out_absorb.dtype, device=out_absorb.device)
self.out_absorb.weight.data = out_absorb
del self.orig_module.kv_b_proj
#del self.orig_module.kv_b_proj
q_absorb = self.q_absorb.weight.view(self.num_heads, self.qk_nope_head_dim, self.kv_lora_rank)
out_absorb = self.out_absorb.weight.view(self.num_heads, self.v_head_dim, self.kv_lora_rank)
return q_absorb, out_absorb
@ -362,60 +167,129 @@ class KDeepseekV2Attention(BaseInjectedModule, DeepseekV2Attention):
cache_position: Optional[torch.LongTensor] = None,
**kwargs,
) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]:
if "padding_mask" in kwargs:
warnings.warn(
"Passing `padding_mask` is deprecated and will be removed in v4.37. Please make sure use `attention_mask` instead.`"
)
bsz, q_len, _ = hidden_states.size()
if q_len <= self.chunck_size:
return self.forward_chunck(
hidden_states,
attention_mask,
position_ids,
past_key_value,
output_attentions,
use_cache,
cache_position,
**kwargs
)
bsz, q_len, _ = hidden_states.size()
assert output_attentions == False, "output_attentions is not supported when using chunked attention"
attn_output = None
cur_idx = 0
while cur_idx < q_len:
if attention_mask is not None:
chunk_mask = attention_mask[:, :, cur_idx:min(cur_idx + self.chunck_size, q_len), ...]
else:
# generate chunk_mask automatically.
self.attn_mask = \
torch.zeros(1, 1, self.chunck_size, past_key_value.max_cache_len, device=hidden_states.device) \
if self.attn_mask is None \
else self.attn_mask
self.attn_mask[:, :, :, cur_idx:min(cur_idx+self.chunck_size, past_key_value.max_cache_len)] = \
-1e+38 * torch.triu(torch.ones(self.chunck_size, self.chunck_size, device=hidden_states.device), diagonal=1)\
[:,:min(self.chunck_size, min(past_key_value.max_cache_len-cur_idx, self.chunck_size))]
self.attn_mask[:, :, :, cur_idx+self.chunck_size:] = -1e+38
self.attn_mask[:, :, :, :cur_idx] = 0
chunk_mask = torch.narrow(self.attn_mask, 2, 0, min(self.chunck_size, q_len-cur_idx))
if self.q_lora_rank is None:
q = self.q_proj(hidden_states)
else:
q = self.q_b_proj(self.q_a_layernorm(self.q_a_proj(hidden_states)))
q = q.view(bsz, q_len, self.num_heads, self.q_head_dim).transpose(1, 2)
q_nope, q_pe = torch.split(
q, [self.qk_nope_head_dim, self.qk_rope_head_dim], dim=-1
)
compressed_kv = self.kv_a_proj_with_mqa(hidden_states)
compressed_kv, k_pe = torch.split(
compressed_kv, [self.kv_lora_rank, self.qk_rope_head_dim], dim=-1
)
compressed_kv = self.kv_a_layernorm(compressed_kv)
k_pe = k_pe.view(bsz, q_len, 1, self.qk_rope_head_dim).transpose(1, 2)
compressed_kv = compressed_kv.view(bsz, q_len, 1, self.kv_lora_rank)
cos, sin = self.rotary_emb(q_pe, position_ids)
q_pe, k_pe = apply_rotary_pos_emb(q_pe, k_pe, cos, sin)
k_pe = k_pe.transpose(1, 2) # [bsz, q_len, 1, self.qk_rope_head_dim]
# decode
if q_len == 1:
if past_key_value is not None:
cache_kwargs = {"sin": sin, "cos": cos, "cache_position": cache_position} # Specific to RoPE models
k_pe, compressed_kv, page_table = past_key_value.update(k_pe, compressed_kv, self.layer_idx, cache_kwargs)
# q_nope [bsz, self.num_heads, q_len, self.qk_nope_head_dim]
# q_absorb [self.num_heads, self.qk_nope_head_dim, self.kv_lora_rank]
q_absorb, out_absorb = self.get_absorbed()
q_nope = torch.matmul(q_nope, q_absorb) # batched MM
# q_nope [bsz, self.num_heads, q_len, self.kv_lora_rank]
# q_pe [bsz, self.num_heads, q_len, self.qk_rope_head_dim]
query_states = torch.cat([q_nope, q_pe], dim=-1)
# k_pe [bsz, q_len, 1, self.qk_rope_head_dim]
# compressed_kv [bsz, q_len, 1, self.kv_lora_rank]
key_states = torch.cat([compressed_kv, k_pe], dim=-1)
query_states = query_states.squeeze(2)
attn_output = torch.zeros_like(q_nope)
attn_logits = torch.empty(
(
bsz,
self.num_heads,
1, #num_kv_splits # follow vLLM, fix it TODO
self.kv_lora_rank + 1,
),
dtype=torch.float32,
device = attn_output.device
)
"""
print("query_states", torch.isnan(query_states).any())
print("key_states", torch.isnan(key_states[:,:,0,:]).any())
print("compressed_kv", torch.isnan(compressed_kv[:,:,0,:]).any())
print("position_ids", torch.isnan(position_ids).any())
"""
# flash attn doesn't support head_dim bigger than 256
# use vLLM triton attention kernel for MQA
decode_attention_fwd_grouped(query_states, key_states, compressed_kv, attn_output,
page_table,
position_ids.squeeze(0).to(torch.int32), attn_logits,
1, #num_kv_splits # follow vLLM, fix it TODO
self.softmax_scale,
past_key_value.page_size)
attn_output = torch.matmul(attn_output, out_absorb.mT)
attn_output = attn_output.transpose(1, 2).contiguous()
attn_output = attn_output.reshape(bsz, q_len, self.num_heads * self.v_head_dim)
attn_output = self.o_proj(attn_output)
#print("attn_output", torch.isnan(attn_output).any())
return attn_output, None, past_key_value
else:
if past_key_value is not None:
cache_kwargs = {"sin": sin, "cos": cos, "cache_position": cache_position} # Specific to RoPE models
k_pe.squeeze(0)
compressed_kv.squeeze(0)
past_key_value.update(k_pe, compressed_kv, self.layer_idx, cache_kwargs)
k_pe.unsqueeze(0)
compressed_kv.unsqueeze(0)
k_pe = k_pe[:, :q_len]
compressed_kv = compressed_kv[:, :q_len]
kv = (
self.kv_b_proj(compressed_kv)
.view(bsz, q_len, self.num_heads, self.qk_nope_head_dim + self.v_head_dim)
)
k_nope, value_states = torch.split(kv, [self.qk_nope_head_dim, self.v_head_dim], dim=-1)
query_states = k_pe.new_empty(bsz, self.num_heads, q_len, self.q_head_dim)
query_states[:, :, :, : self.qk_nope_head_dim] = q_nope
query_states[:, :, :, self.qk_nope_head_dim :] = q_pe
key_states = k_pe.new_empty(bsz, q_len, self.num_heads, self.q_head_dim)
key_states[:, :, :, :self.qk_nope_head_dim] = k_nope
key_states[:, :, :, self.qk_nope_head_dim:] = k_pe
query_states = query_states.transpose(1, 2)
value_states = value_states.view(bsz, q_len, self.num_heads, self.v_head_dim)
value_states_padded = torch.nn.functional.pad(value_states, [0, query_states.shape[-1] - value_states.shape[-1]], value=0)
attn_output = flash_attn_func(
query_states,
key_states,
value_states_padded,
softmax_scale=self.softmax_scale,
causal=True,
)
if self.q_head_dim != self.v_head_dim:
attn_output = attn_output[:, :, :, : self.v_head_dim]
attn_output = attn_output.reshape(
bsz, q_len, self.num_heads * self.v_head_dim
).contiguous()
attn_output = self.o_proj(attn_output)
return attn_output, None, past_key_value
cur_output, _, _ = self.forward_chunck(
hidden_states[:, cur_idx:min(cur_idx + self.chunck_size, q_len), ...],
chunk_mask,
position_ids[:, cur_idx:min(cur_idx + self.chunck_size, q_len)],
past_key_value,
output_attentions,
use_cache,
cache_position[cur_idx:min(cur_idx + self.chunck_size, q_len)],
**kwargs
)
cur_idx += self.chunck_size
if attn_output is None:
attn_output = cur_output
else:
attn_output = torch.cat((attn_output, cur_output), dim=-2)
return attn_output, None, past_key_value
def rotate_half(x):
"""Rotates half the hidden dims of the input."""
x1 = x[..., : x.shape[-1] // 2]
@ -423,8 +297,6 @@ def rotate_half(x):
return torch.cat((-x2, x1), dim=-1)
class KLlamaAttention(BaseInjectedModule):
"""Multi-headed attention from 'Attention Is All You Need' paper"""

379
ktransformers/operators/triton_attention.py Normal file
View file

@ -0,0 +1,379 @@
import triton
import triton.language as tl
@triton.jit
def tanh(x):
# Tanh is just a scaled sigmoid
return 2 * tl.sigmoid(2 * x) - 1
@triton.jit
def _fwd_grouped_kernel_stage1(
Q,
K_Buffer,
V_Buffer,
sm_scale,
Req_to_tokens,
B_Seqlen,
Att_Out,
stride_req_to_tokens_b,
stride_qbs,
stride_qh,
stride_buf_kbs,
stride_buf_kh,
stride_buf_vbs,
stride_buf_vh,
stride_mid_ob,
stride_mid_oh,
stride_mid_os,
kv_group_num: tl.constexpr,
q_head_num: tl.constexpr,
BLOCK_DMODEL: tl.constexpr,
BLOCK_DPE: tl.constexpr,
BLOCK_DV: tl.constexpr,
BLOCK_N: tl.constexpr,
BLOCK_H: tl.constexpr,
NUM_KV_SPLITS: tl.constexpr,
PAGE_SIZE: tl.constexpr,
logit_cap: tl.constexpr,
Lk: tl.constexpr,
Lv: tl.constexpr,
):
cur_batch = tl.program_id(0)
cur_head_id = tl.program_id(1)
cur_kv_head = cur_head_id // tl.cdiv(kv_group_num, BLOCK_H)
split_kv_id = tl.program_id(2)
if kv_group_num > BLOCK_H:
VALID_BLOCK_H: tl.constexpr = BLOCK_H
else:
VALID_BLOCK_H: tl.constexpr = kv_group_num
cur_head = cur_head_id * VALID_BLOCK_H + tl.arange(0, BLOCK_H)
mask_h = cur_head < (cur_head_id + 1) * VALID_BLOCK_H
mask_h = mask_h & (cur_head < q_head_num)
offs_d = tl.arange(0, BLOCK_DMODEL)
offs_dv = tl.arange(0, BLOCK_DV)
mask_d = offs_d < Lk
mask_dv = offs_dv < Lv
cur_batch_seq_len = tl.load(B_Seqlen + cur_batch)
cur_batch_req_idx = cur_batch
offs_q = cur_batch * stride_qbs + cur_head[:, None] * stride_qh + offs_d[
None, :]
q = tl.load(Q + offs_q,
mask=(mask_h[:, None]) & (mask_d[None, :]),
other=0.0)
if BLOCK_DPE > 0:
offs_dpe = BLOCK_DMODEL + tl.arange(0, BLOCK_DPE)
mask_dpe = offs_dpe < Lk
off_qpe = (cur_batch * stride_qbs + cur_head[:, None] * stride_qh +
offs_dpe[None, :])
qpe = tl.load(Q + off_qpe,
mask=(mask_h[:, None]) & (mask_dpe[None, :]),
other=0.0)
kv_len_per_split = tl.cdiv(cur_batch_seq_len, NUM_KV_SPLITS)
split_kv_start = kv_len_per_split * split_kv_id
split_kv_end = tl.minimum(split_kv_start + kv_len_per_split,
cur_batch_seq_len)
e_max = tl.zeros([BLOCK_H], dtype=tl.float32) - float("inf")
e_sum = tl.zeros([BLOCK_H], dtype=tl.float32)
acc = tl.zeros([BLOCK_H, BLOCK_DV], dtype=tl.float32)
if split_kv_end > split_kv_start:
for start_n in range(split_kv_start, split_kv_end, BLOCK_N):
offs_n = start_n + tl.arange(0, BLOCK_N)
kv_page_number = tl.load(
Req_to_tokens + stride_req_to_tokens_b * cur_batch_req_idx +
offs_n // PAGE_SIZE,
mask=offs_n < split_kv_end,
other=0,
)
kv_loc = kv_page_number * PAGE_SIZE + offs_n % PAGE_SIZE
offs_buf_k = (kv_loc[None, :] * stride_buf_kbs +
cur_kv_head * stride_buf_kh + offs_d[:, None])
k = tl.load(
K_Buffer + offs_buf_k,
mask=(offs_n[None, :] < split_kv_end) & (mask_d[:, None]),
other=0.0,
)
qk = tl.dot(q, k.to(q.dtype))
if BLOCK_DPE > 0:
offs_buf_kpe = (kv_loc[None, :] * stride_buf_kbs +
cur_kv_head * stride_buf_kh +
offs_dpe[:, None])
kpe = tl.load(
K_Buffer + offs_buf_kpe,
mask=(offs_n[None, :] < split_kv_end) &
(mask_dpe[:, None]),
other=0.0,
)
qk += tl.dot(qpe, kpe.to(qpe.dtype))
qk *= sm_scale
if logit_cap > 0:
qk = logit_cap * tanh(qk / logit_cap)
qk = tl.where(mask_h[:, None] & (offs_n[None, :] < split_kv_end),
qk, float("-inf"))
offs_buf_v = (kv_loc[:, None] * stride_buf_vbs +
cur_kv_head * stride_buf_vh + offs_dv[None, :])
v = tl.load(
V_Buffer + offs_buf_v,
mask=(offs_n[:, None] < split_kv_end) & (mask_dv[None, :]),
other=0.0,
)
n_e_max = tl.maximum(tl.max(qk, 1), e_max)
re_scale = tl.exp(e_max - n_e_max)
p = tl.exp(qk - n_e_max[:, None])
acc *= re_scale[:, None]
acc += tl.dot(p.to(v.dtype), v)
e_sum = e_sum * re_scale + tl.sum(p, 1)
e_max = n_e_max
offs_mid_o = (cur_batch * stride_mid_ob +
cur_head[:, None] * stride_mid_oh +
split_kv_id * stride_mid_os + offs_dv[None, :])
tl.store(
Att_Out + offs_mid_o,
acc / e_sum[:, None],
mask=(mask_h[:, None]) & (mask_dv[None, :]),
)
offs_mid_o_1 = (cur_batch * stride_mid_ob + cur_head * stride_mid_oh +
split_kv_id * stride_mid_os + Lv)
tl.store(
Att_Out + offs_mid_o_1,
e_max + tl.log(e_sum),
mask=mask_h,
)
def _decode_grouped_att_m_fwd(
q,
k_buffer,
v_buffer,
att_out,
Req_to_tokens,
B_Seqlen,
num_kv_splits,
sm_scale,
page_size,
logit_cap,
):
BLOCK = 32
Lk = k_buffer.shape[-1]
Lv = v_buffer.shape[-1]
# [TODO] work around shmem limit on MI3xx
# TODO: support hip
#if is_hip_ and Lk >= 576:
# BLOCK = 16
if Lk == 576:
BLOCK_DMODEL = 512
BLOCK_DPE = 64
elif Lk == 288:
BLOCK_DMODEL = 256
BLOCK_DPE = 32
else:
BLOCK_DMODEL = triton.next_power_of_2(Lk)
BLOCK_DPE = 0
BLOCK_DV = triton.next_power_of_2(Lv)
batch, head_num = q.shape[0], q.shape[1]
kv_group_num = q.shape[1] // k_buffer.shape[-2]
BLOCK_H = 16
NUM_KV_SPLITS = num_kv_splits
grid = (
batch,
triton.cdiv(head_num, min(BLOCK_H, kv_group_num)),
NUM_KV_SPLITS,
)
extra_kargs = {}
# TODO: support hip
"""
if is_hip_:
# https://rocm.docs.amd.com/en/docs-6.2.0/how-to/llm-fine-tuning-optimization/optimizing-triton-kernel.html
# https://github.com/triton-lang/triton/blob/main/third_party/amd/backend/compiler.py
extra_kargs = {
"waves_per_eu": 4,
"matrix_instr_nonkdim": 16,
"kpack": 2
}
"""
_fwd_grouped_kernel_stage1[grid](
q,
k_buffer,
v_buffer,
sm_scale,
Req_to_tokens,
B_Seqlen,
att_out,
Req_to_tokens.stride(0),
q.stride(0),
q.stride(1),
k_buffer.stride(-3), # Assume (..., PAGE_SIZE, NUM_HEADS, HEAD_DIM)
k_buffer.stride(-2), # Assume (..., PAGE_SIZE, NUM_HEADS, HEAD_DIM)
v_buffer.stride(-3), # Assume (..., PAGE_SIZE, NUM_HEADS, HEAD_DIM)
v_buffer.stride(-2), # Assume (..., PAGE_SIZE, NUM_HEADS, HEAD_DIM)
att_out.stride(0),
att_out.stride(1),
att_out.stride(2),
kv_group_num=kv_group_num,
q_head_num=head_num,
BLOCK_DMODEL=BLOCK_DMODEL,
BLOCK_DPE=BLOCK_DPE,
BLOCK_DV=BLOCK_DV,
BLOCK_N=BLOCK,
BLOCK_H=BLOCK_H,
NUM_KV_SPLITS=NUM_KV_SPLITS,
PAGE_SIZE=page_size,
logit_cap=logit_cap,
num_warps=4,
num_stages=2,
Lk=Lk,
Lv=Lv,
**extra_kargs,
)
@triton.jit
def _fwd_kernel_stage2(
Mid_O,
o,
B_Seqlen,
stride_mid_ob,
stride_mid_oh,
stride_mid_os,
stride_obs,
stride_oh,
NUM_KV_SPLITS: tl.constexpr,
BLOCK_DV: tl.constexpr,
Lv: tl.constexpr,
):
cur_batch = tl.program_id(0)
cur_head = tl.program_id(1)
cur_batch_seq_len = tl.load(B_Seqlen + cur_batch)
offs_d = tl.arange(0, BLOCK_DV)
mask_d = offs_d < Lv
e_sum = 0.0
e_max = -float("inf")
acc = tl.zeros([BLOCK_DV], dtype=tl.float32)
offs_v = cur_batch * stride_mid_ob + cur_head * stride_mid_oh + offs_d
offs_logic = cur_batch * stride_mid_ob + cur_head * stride_mid_oh + Lv
for split_kv_id in range(0, NUM_KV_SPLITS):
kv_len_per_split = tl.cdiv(cur_batch_seq_len, NUM_KV_SPLITS)
split_kv_start = kv_len_per_split * split_kv_id
split_kv_end = tl.minimum(split_kv_start + kv_len_per_split,
cur_batch_seq_len)
if split_kv_end > split_kv_start:
tv = tl.load(Mid_O + offs_v + split_kv_id * stride_mid_os,
mask=mask_d,
other=0.0)
tlogic = tl.load(Mid_O + offs_logic + split_kv_id * stride_mid_os)
n_e_max = tl.maximum(tlogic, e_max)
old_scale = tl.exp(e_max - n_e_max)
acc *= old_scale
exp_logic = tl.exp(tlogic - n_e_max)
acc += exp_logic * tv
e_sum = e_sum * old_scale + exp_logic
e_max = n_e_max
tl.store(
o + cur_batch * stride_obs + cur_head * stride_oh + offs_d,
acc / e_sum,
mask=mask_d,
)
def _decode_softmax_reducev_fwd(
logits,
q,
o,
v_buffer,
b_seq_len,
num_kv_splits,
):
batch, head_num = q.shape[0], q.shape[1]
Lv = v_buffer.shape[-1]
BLOCK_DV = triton.next_power_of_2(Lv)
NUM_KV_SPLITS = num_kv_splits
extra_kargs = {}
# TODO: support hip
"""
if is_hip_:
# https://rocm.docs.amd.com/en/docs-6.2.0/how-to/llm-fine-tuning-optimization/optimizing-triton-kernel.html
# https://github.com/triton-lang/triton/blob/main/third_party/amd/backend/compiler.py
extra_kargs = {
"waves_per_eu": 4,
"matrix_instr_nonkdim": 16,
"kpack": 2
}
"""
grid = (batch, head_num)
_fwd_kernel_stage2[grid](
logits,
o,
b_seq_len,
logits.stride(0),
logits.stride(1),
logits.stride(2),
o.stride(0),
o.stride(1),
NUM_KV_SPLITS=NUM_KV_SPLITS,
BLOCK_DV=BLOCK_DV,
Lv=Lv,
num_warps=4,
num_stages=2,
**extra_kargs,
)
def decode_attention_fwd_grouped(
q,
k_buffer,
v_buffer,
o,
req_to_token,
b_seq_len,
attn_logits,
num_kv_splits,
sm_scale,
page_size,
logit_cap=0.0,
):
_decode_grouped_att_m_fwd(
q,
k_buffer,
v_buffer,
attn_logits,
req_to_token,
b_seq_len,
num_kv_splits,
sm_scale,
page_size,
logit_cap,
)
_decode_softmax_reducev_fwd(attn_logits, q, o, v_buffer, b_seq_len,
num_kv_splits)

4
ktransformers/util/utils.py
View file

@ -133,7 +133,7 @@ def prefill_and_generate(model, tokenizer, inputs, max_new_tokens=10000, use_cud
)
else:
past_key_values = None
cache_position = torch.arange(seq_length, device=torch_device)
cache_position = torch.arange(seq_length, device=torch_device, dtype=torch.long)
generated_ids = torch.zeros(
batch_size, seq_length + max_new_tokens + 1, dtype=torch.int, device=torch_device
)
@ -178,7 +178,7 @@ def prefill_and_generate(model, tokenizer, inputs, max_new_tokens=10000, use_cud
generated_ids[:, seq_length] = next_token
tokens.append(int(next_token))
inputs = torch.cat((inputs, next_token.unsqueeze(0)), dim=-1)
cache_position = torch.tensor([seq_length], device=torch_device)
cache_position = torch.tensor([seq_length], device=torch_device, dtype=torch.long)
position_ids = cache_position.unsqueeze(0)
seq_length += 1

9
test_prompt.txt Normal file
View file

@ -0,0 +1,9 @@
Mr. and Mrs. Dursley, of number four, Privet Drive, were proud to say that they were perfectly normal, thank you very much. They were the last people you'd expect to be involved in anything strange or mysterious, because they just didn't hold with such nonsense. Mr. Dursley was the director of a firm called Grunnings, which made drills. He was a big, beefy man with hardly any neck, although he did have a very large mustache. Mrs. Dursley was thin and blonde and had nearly twice the usual amount of neck, which came in very useful as she spent so much of her time craning over garden fences, spying on the neighbors. The Dursleys had a small son called Dudley and in their opinion there was no finer boy anywhere. The Dursleys had everything they wanted, but they also had a secret, and their greatest fear was that somebody would discover it. They didn't think they could bear it if anyone found out about the Potters. Mrs. Potter was Mrs. Dursley's sister, but they hadn't met for several years; in fact, Mrs. Dursley pretended she didn't have a sister, because her sister and her good-for-nothing husband were as unDursleyish as it was possible to be. The Dursleys shuddered to think what the neighbors would say if the Potters arrived in the street. The Dursleys knew that the Potters had a small son, too, but they had never even seen him. This boy was another good reason for keeping the Potters away; they didn't want Dudley mixing with a child like that.When Mr. and Mrs. Dursley woke up on the dull, gray Tuesday our story starts, there was nothing about the cloudy sky outside to suggest that strange and mysterious things would soon be happening all over the country. Mr. Dursley hummed as he picked out his most boring tie for work, and Mrs. Dursley gossiped away happily as she wrestled a screaming Dudley into his high chair. None of them noticed a large, tawny owl flutter past the window. At half past eight, Mr. Dursley picked up his briefcase, pecked Mrs. Dursley on the cheek, and tried to kiss Dudley good-bye but missed, because Dudley was now having a tantrum and throwing his cereal at the walls. “Little tyke,” chortled Mr. Dursley as he left the house. He got into his car and backed out of number four's drive. It was on the corner of the street that he noticed the first sign of something peculiar — a cat reading a map. For a second, Mr. Dursley didn't realize what he had seen — then he jerked his head around to look again. There was a tabby cat standing on the corner of Privet Drive, but there wasn't a map in sight. What could he have been thinking of? It must have been a trick of the light. Mr. Dursley blinked and stared at the cat. It stared back. As Mr. Dursley drove around the corner and up the road, he watched the cat in his mirror. It was now reading the sign that said Privet Drive — no, looking at the sign; cats couldn't read maps or signs. Mr. Dursley gave himself a little shake and put the cat out of his mind. As he drove toward town he thought of nothing except a large order of drills he was hoping to get that day. But on the edge of town, drills were driven out of his mind by something else. As he sat in the usual morning traffic jam, he couldn't help noticing that there seemed to be a lot of strangely dressed people about. People in cloaks. Mr. Dursley couldn't bear people who dressed in funny clothes — the getups you saw on young people! He supposed this was some stupid new fashion. He drummed his fingers on the steering wheel and his eyes fell on a huddle of these weirdos standing quite close by. They were whispering excitedly together. Mr. Dursley was enraged to see that a couple of them weren't young at all; why, that man had to be older than he was, and wearing an emerald-green cloak! The nerve of him! But then it struck Mr. Dursley that this was probably some silly stunt — these people were obviously collecting for something… yes, that would be it. The traffic moved on and a few minutes later, Mr. Dursley arrived in the Grunnings parking lot, his mind back on drills.
Mr. and Mrs. Dursley, of number four, Privet Drive, were proud to say that they were perfectly normal, thank you very much. They were the last people you'd expect to be involved in anything strange or mysterious, because they just didn't hold with such nonsense. Mr. Dursley was the director of a firm called Grunnings, which made drills. He was a big, beefy man with hardly any neck, although he did have a very large mustache. Mrs. Dursley was thin and blonde and had nearly twice the usual amount of neck, which came in very useful as she spent so much of her time craning over garden fences, spying on the neighbors. The Dursleys had a small son called Dudley and in their opinion there was no finer boy anywhere. The Dursleys had everything they wanted, but they also had a secret, and their greatest fear was that somebody would discover it. They didn't think they could bear it if anyone found out about the Potters. Mrs. Potter was Mrs. Dursley's sister, but they hadn't met for several years; in fact, Mrs. Dursley pretended she didn't have a sister, because her sister and her good-for-nothing husband were as unDursleyish as it was possible to be. The Dursleys shuddered to think what the neighbors would say if the Potters arrived in the street. The Dursleys knew that the Potters had a small son, too, but they had never even seen him. This boy was another good reason for keeping the Potters away; they didn't want Dudley mixing with a child like that.When Mr. and Mrs. Dursley woke up on the dull, gray Tuesday our story starts, there was nothing about the cloudy sky outside to suggest that strange and mysterious things would soon be happening all over the country. Mr. Dursley hummed as he picked out his most boring tie for work, and Mrs. Dursley gossiped away happily as she wrestled a screaming Dudley into his high chair. None of them noticed a large, tawny owl flutter past the window. At half past eight, Mr. Dursley picked up his briefcase, pecked Mrs. Dursley on the cheek, and tried to kiss Dudley good-bye but missed, because Dudley was now having a tantrum and throwing his cereal at the walls. “Little tyke,” chortled Mr. Dursley as he left the house. He got into his car and backed out of number four's drive. It was on the corner of the street that he noticed the first sign of something peculiar — a cat reading a map. For a second, Mr. Dursley didn't realize what he had seen — then he jerked his head around to look again. There was a tabby cat standing on the corner of Privet Drive, but there wasn't a map in sight. What could he have been thinking of? It must have been a trick of the light. Mr. Dursley blinked and stared at the cat. It stared back. As Mr. Dursley drove around the corner and up the road, he watched the cat in his mirror. It was now reading the sign that said Privet Drive — no, looking at the sign; cats couldn't read maps or signs. Mr. Dursley gave himself a little shake and put the cat out of his mind. As he drove toward town he thought of nothing except a large order of drills he was hoping to get that day. But on the edge of town, drills were driven out of his mind by something else. As he sat in the usual morning traffic jam, he couldn't help noticing that there seemed to be a lot of strangely dressed people about. People in cloaks. Mr. Dursley couldn't bear people who dressed in funny clothes — the getups you saw on young people! He supposed this was some stupid new fashion. He drummed his fingers on the steering wheel and his eyes fell on a huddle of these weirdos standing quite close by. They were whispering excitedly together. Mr. Dursley was enraged to see that a couple of them weren't young at all; why, that man had to be older than he was, and wearing an emerald-green cloak! The nerve of him! But then it struck Mr. Dursley that this was probably some silly stunt — these people were obviously collecting for something… yes, that would be it. The traffic moved on and a few minutes later, Mr. Dursley arrived in the Grunnings parking lot, his mind back on drills.
Mr. and Mrs. Dursley, of number four, Privet Drive, were proud to say that they were perfectly normal, thank you very much. They were the last people you'd expect to be involved in anything strange or mysterious, because they just didn't hold with such nonsense. Mr. Dursley was the director of a firm called Grunnings, which made drills. He was a big, beefy man with hardly any neck, although he did have a very large mustache. Mrs. Dursley was thin and blonde and had nearly twice the usual amount of neck, which came in very useful as she spent so much of her time craning over garden fences, spying on the neighbors. The Dursleys had a small son called Dudley and in their opinion there was no finer boy anywhere. The Dursleys had everything they wanted, but they also had a secret, and their greatest fear was that somebody would discover it. They didn't think they could bear it if anyone found out about the Potters. Mrs. Potter was Mrs. Dursley's sister, but they hadn't met for several years; in fact, Mrs. Dursley pretended she didn't have a sister, because her sister and her good-for-nothing husband were as unDursleyish as it was possible to be. The Dursleys shuddered to think what the neighbors would say if the Potters arrived in the street. The Dursleys knew that the Potters had a small son, too, but they had never even seen him. This boy was another good reason for keeping the Potters away; they didn't want Dudley mixing with a child like that.When Mr. and Mrs. Dursley woke up on the dull, gray Tuesday our story starts, there was nothing about the cloudy sky outside to suggest that strange and mysterious things would soon be happening all over the country. Mr. Dursley hummed as he picked out his most boring tie for work, and Mrs. Dursley gossiped away happily as she wrestled a screaming Dudley into his high chair. None of them noticed a large, tawny owl flutter past the window. At half past eight, Mr. Dursley picked up his briefcase, pecked Mrs. Dursley on the cheek, and tried to kiss Dudley good-bye but missed, because Dudley was now having a tantrum and throwing his cereal at the walls. “Little tyke,” chortled Mr. Dursley as he left the house. He got into his car and backed out of number four's drive. It was on the corner of the street that he noticed the first sign of something peculiar — a cat reading a map. For a second, Mr. Dursley didn't realize what he had seen — then he jerked his head around to look again. There was a tabby cat standing on the corner of Privet Drive, but there wasn't a map in sight. What could he have been thinking of? It must have been a trick of the light. Mr. Dursley blinked and stared at the cat. It stared back. As Mr. Dursley drove around the corner and up the road, he watched the cat in his mirror. It was now reading the sign that said Privet Drive — no, looking at the sign; cats couldn't read maps or signs. Mr. Dursley gave himself a little shake and put the cat out of his mind. As he drove toward town he thought of nothing except a large order of drills he was hoping to get that day. But on the edge of town, drills were driven out of his mind by something else. As he sat in the usual morning traffic jam, he couldn't help noticing that there seemed to be a lot of strangely dressed people about. People in cloaks. Mr. Dursley couldn't bear people who dressed in funny clothes — the getups you saw on young people! He supposed this was some stupid new fashion. He drummed his fingers on the steering wheel and his eyes fell on a huddle of these weirdos standing quite close by. They were whispering excitedly together. Mr. Dursley was enraged to see that a couple of them weren't young at all; why, that man had to be older than he was, and wearing an emerald-green cloak! The nerve of him! But then it struck Mr. Dursley that this was probably some silly stunt — these people were obviously collecting for something… yes, that would be it. The traffic moved on and a few minutes later, Mr. Dursley arrived in the Grunnings parking lot, his mind back on drills.
Mr. and Mrs. Dursley, of number four, Privet Drive, were proud to say that they were perfectly normal, thank you very much. They were the last people you'd expect to be involved in anything strange or mysterious, because they just didn't hold with such nonsense. Mr. Dursley was the director of a firm called Grunnings, which made drills. He was a big, beefy man with hardly any neck, although he did have a very large mustache. Mrs. Dursley was thin and blonde and had nearly twice the usual amount of neck, which came in very useful as she spent so much of her time craning over garden fences, spying on the neighbors. The Dursleys had a small son called Dudley and in their opinion there was no finer boy anywhere. The Dursleys had everything they wanted, but they also had a secret, and their greatest fear was that somebody would discover it. They didn't think they could bear it if anyone found out about the Potters. Mrs. Potter was Mrs. Dursley's sister, but they hadn't met for several years; in fact, Mrs. Dursley pretended she didn't have a sister, because her sister and her good-for-nothing husband were as unDursleyish as it was possible to be. The Dursleys shuddered to think what the neighbors would say if the Potters arrived in the street. The Dursleys knew that the Potters had a small son, too, but they had never even seen him. This boy was another good reason for keeping the Potters away; they didn't want Dudley mixing with a child like that.When Mr. and Mrs. Dursley woke up on the dull, gray Tuesday our story starts, there was nothing about the cloudy sky outside to suggest that strange and mysterious things would soon be happening all over the country. Mr. Dursley hummed as he picked out his most boring tie for work, and Mrs. Dursley gossiped away happily as she wrestled a screaming Dudley into his high chair. None of them noticed a large, tawny owl flutter past the window. At half past eight, Mr. Dursley picked up his briefcase, pecked Mrs. Dursley on the cheek, and tried to kiss Dudley good-bye but missed, because Dudley was now having a tantrum and throwing his cereal at the walls. “Little tyke,” chortled Mr. Dursley as he left the house. He got into his car and backed out of number four's drive. It was on the corner of the street that he noticed the first sign of something peculiar — a cat reading a map. For a second, Mr. Dursley didn't realize what he had seen — then he jerked his head around to look again. There was a tabby cat standing on the corner of Privet Drive, but there wasn't a map in sight. What could he have been thinking of? It must have been a trick of the light. Mr. Dursley blinked and stared at the cat. It stared back. As Mr. Dursley drove around the corner and up the road, he watched the cat in his mirror. It was now reading the sign that said Privet Drive — no, looking at the sign; cats couldn't read maps or signs. Mr. Dursley gave himself a little shake and put the cat out of his mind. As he drove toward town he thought of nothing except a large order of drills he was hoping to get that day. But on the edge of town, drills were driven out of his mind by something else. As he sat in the usual morning traffic jam, he couldn't help noticing that there seemed to be a lot of strangely dressed people about. People in cloaks. Mr. Dursley couldn't bear people who dressed in funny clothes — the getups you saw on young people! He supposed this was some stupid new fashion. He drummed his fingers on the steering wheel and his eyes fell on a huddle of these weirdos standing quite close by. They were whispering excitedly together. Mr. Dursley was enraged to see that a couple of them weren't young at all; why, that man had to be older than he was, and wearing an emerald-green cloak! The nerve of him! But then it struck Mr. Dursley that this was probably some silly stunt — these people were obviously collecting for something… yes, that would be it. The traffic moved on and a few minutes later, Mr. Dursley arrived in the Grunnings parking lot, his mind back on drills.
Mr. and Mrs. Dursley, of number four, Privet Drive, were proud to say that they were perfectly normal, thank you very much. They were the last people you'd expect to be involved in anything strange or mysterious, because they just didn't hold with such nonsense. Mr. Dursley was the director of a firm called Grunnings, which made drills. He was a big, beefy man with hardly any neck, although he did have a very large mustache. Mrs. Dursley was thin and blonde and had nearly twice the usual amount of neck, which came in very useful as she spent so much of her time craning over garden fences, spying on the neighbors. The Dursleys had a small son called Dudley and in their opinion there was no finer boy anywhere. The Dursleys had everything they wanted, but they also had a secret, and their greatest fear was that somebody would discover it. They didn't think they could bear it if anyone found out about the Potters. Mrs. Potter was Mrs. Dursley's sister, but they hadn't met for several years; in fact, Mrs. Dursley pretended she didn't have a sister, because her sister and her good-for-nothing husband were as unDursleyish as it was possible to be. The Dursleys shuddered to think what the neighbors would say if the Potters arrived in the street. The Dursleys knew that the Potters had a small son, too, but they had never even seen him. This boy was another good reason for keeping the Potters away; they didn't want Dudley mixing with a child like that.When Mr. and Mrs. Dursley woke up on the dull, gray Tuesday our story starts, there was nothing about the cloudy sky outside to suggest that strange and mysterious things would soon be happening all over the country. Mr. Dursley hummed as he picked out his most boring tie for work, and Mrs. Dursley gossiped away happily as she wrestled a screaming Dudley into his high chair. None of them noticed a large, tawny owl flutter past the window. At half past eight, Mr. Dursley picked up his briefcase, pecked Mrs. Dursley on the cheek, and tried to kiss Dudley good-bye but missed, because Dudley was now having a tantrum and throwing his cereal at the walls. “Little tyke,” chortled Mr. Dursley as he left the house. He got into his car and backed out of number four's drive. It was on the corner of the street that he noticed the first sign of something peculiar — a cat reading a map. For a second, Mr. Dursley didn't realize what he had seen — then he jerked his head around to look again. There was a tabby cat standing on the corner of Privet Drive, but there wasn't a map in sight. What could he have been thinking of? It must have been a trick of the light. Mr. Dursley blinked and stared at the cat. It stared back. As Mr. Dursley drove around the corner and up the road, he watched the cat in his mirror. It was now reading the sign that said Privet Drive — no, looking at the sign; cats couldn't read maps or signs. Mr. Dursley gave himself a little shake and put the cat out of his mind. As he drove toward town he thought of nothing except a large order of drills he was hoping to get that day. But on the edge of town, drills were driven out of his mind by something else. As he sat in the usual morning traffic jam, he couldn't help noticing that there seemed to be a lot of strangely dressed people about. People in cloaks. Mr. Dursley couldn't bear people who dressed in funny clothes — the getups you saw on young people! He supposed this was some stupid new fashion. He drummed his fingers on the steering wheel and his eyes fell on a huddle of these weirdos standing quite close by. They were whispering excitedly together. Mr. Dursley was enraged to see that a couple of them weren't young at all; why, that man had to be older than he was, and wearing an emerald-green cloak! The nerve of him! But then it struck Mr. Dursley that this was probably some silly stunt — these people were obviously collecting for something… yes, that would be it. The traffic moved on and a few minutes later, Mr. Dursley arrived in the Grunnings parking lot, his mind back on drills.
Mr. and Mrs. Dursley, of number four, Privet Drive, were proud to say that they were perfectly normal, thank you very much. They were the last people you'd expect to be involved in anything strange or mysterious, because they just didn't hold with such nonsense. Mr. Dursley was the director of a firm called Grunnings, which made drills. He was a big, beefy man with hardly any neck, although he did have a very large mustache. Mrs. Dursley was thin and blonde and had nearly twice the usual amount of neck, which came in very useful as she spent so much of her time craning over garden fences, spying on the neighbors. The Dursleys had a small son called Dudley and in their opinion there was no finer boy anywhere. The Dursleys had everything they wanted, but they also had a secret, and their greatest fear was that somebody would discover it. They didn't think they could bear it if anyone found out about the Potters. Mrs. Potter was Mrs. Dursley's sister, but they hadn't met for several years; in fact, Mrs. Dursley pretended she didn't have a sister, because her sister and her good-for-nothing husband were as unDursleyish as it was possible to be. The Dursleys shuddered to think what the neighbors would say if the Potters arrived in the street. The Dursleys knew that the Potters had a small son, too, but they had never even seen him. This boy was another good reason for keeping the Potters away; they didn't want Dudley mixing with a child like that.When Mr. and Mrs. Dursley woke up on the dull, gray Tuesday our story starts, there was nothing about the cloudy sky outside to suggest that strange and mysterious things would soon be happening all over the country. Mr. Dursley hummed as he picked out his most boring tie for work, and Mrs. Dursley gossiped away happily as she wrestled a screaming Dudley into his high chair. None of them noticed a large, tawny owl flutter past the window. At half past eight, Mr. Dursley picked up his briefcase, pecked Mrs. Dursley on the cheek, and tried to kiss Dudley good-bye but missed, because Dudley was now having a tantrum and throwing his cereal at the walls. “Little tyke,” chortled Mr. Dursley as he left the house. He got into his car and backed out of number four's drive. It was on the corner of the street that he noticed the first sign of something peculiar — a cat reading a map. For a second, Mr. Dursley didn't realize what he had seen — then he jerked his head around to look again. There was a tabby cat standing on the corner of Privet Drive, but there wasn't a map in sight. What could he have been thinking of? It must have been a trick of the light. Mr. Dursley blinked and stared at the cat. It stared back. As Mr. Dursley drove around the corner and up the road, he watched the cat in his mirror. It was now reading the sign that said Privet Drive — no, looking at the sign; cats couldn't read maps or signs. Mr. Dursley gave himself a little shake and put the cat out of his mind. As he drove toward town he thought of nothing except a large order of drills he was hoping to get that day. But on the edge of town, drills were driven out of his mind by something else. As he sat in the usual morning traffic jam, he couldn't help noticing that there seemed to be a lot of strangely dressed people about. People in cloaks. Mr. Dursley couldn't bear people who dressed in funny clothes — the getups you saw on young people! He supposed this was some stupid new fashion. He drummed his fingers on the steering wheel and his eyes fell on a huddle of these weirdos standing quite close by. They were whispering excitedly together. Mr. Dursley was enraged to see that a couple of them weren't young at all; why, that man had to be older than he was, and wearing an emerald-green cloak! The nerve of him! But then it struck Mr. Dursley that this was probably some silly stunt — these people were obviously collecting for something… yes, that would be it. The traffic moved on and a few minutes later, Mr. Dursley arrived in the Grunnings parking lot, his mind back on drills.
Mr. and Mrs. Dursley, of number four, Privet Drive, were proud to say that they were perfectly normal, thank you very much. They were the last people you'd expect to be involved in anything strange or mysterious, because they just didn't hold with such nonsense. Mr. Dursley was the director of a firm called Grunnings, which made drills. He was a big, beefy man with hardly any neck, although he did have a very large mustache. Mrs. Dursley was thin and blonde and had nearly twice the usual amount of neck, which came in very useful as she spent so much of her time craning over garden fences, spying on the neighbors. The Dursleys had a small son called Dudley and in their opinion there was no finer boy anywhere. The Dursleys had everything they wanted, but they also had a secret, and their greatest fear was that somebody would discover it. They didn't think they could bear it if anyone found out about the Potters. Mrs. Potter was Mrs. Dursley's sister, but they hadn't met for several years; in fact, Mrs. Dursley pretended she didn't have a sister, because her sister and her good-for-nothing husband were as unDursleyish as it was possible to be. The Dursleys shuddered to think what the neighbors would say if the Potters arrived in the street. The Dursleys knew that the Potters had a small son, too, but they had never even seen him. This boy was another good reason for keeping the Potters away; they didn't want Dudley mixing with a child like that.When Mr. and Mrs. Dursley woke up on the dull, gray Tuesday our story starts, there was nothing about the cloudy sky outside to suggest that strange and mysterious things would soon be happening all over the country. Mr. Dursley hummed as he picked out his most boring tie for work, and Mrs. Dursley gossiped away happily as she wrestled a screaming Dudley into his high chair. None of them noticed a large, tawny owl flutter past the window. At half past eight, Mr. Dursley picked up his briefcase, pecked Mrs. Dursley on the cheek, and tried to kiss Dudley good-bye but missed, because Dudley was now having a tantrum and throwing his cereal at the walls. “Little tyke,” chortled Mr. Dursley as he left the house. He got into his car and backed out of number four's drive. It was on the corner of the street that he noticed the first sign of something peculiar — a cat reading a map. For a second, Mr. Dursley didn't realize what he had seen — then he jerked his head around to look again. There was a tabby cat standing on the corner of Privet Drive, but there wasn't a map in sight. What could he have been thinking of? It must have been a trick of the light. Mr. Dursley blinked and stared at the cat. It stared back. As Mr. Dursley drove around the corner and up the road, he watched the cat in his mirror. It was now reading the sign that said Privet Drive — no, looking at the sign; cats couldn't read maps or signs. Mr. Dursley gave himself a little shake and put the cat out of his mind. As he drove toward town he thought of nothing except a large order of drills he was hoping to get that day. But on the edge of town, drills were driven out of his mind by something else. As he sat in the usual morning traffic jam, he couldn't help noticing that there seemed to be a lot of strangely dressed people about. People in cloaks. Mr. Dursley couldn't bear people who dressed in funny clothes — the getups you saw on young people! He supposed this was some stupid new fashion. He drummed his fingers on the steering wheel and his eyes fell on a huddle of these weirdos standing quite close by. They were whispering excitedly together. Mr. Dursley was enraged to see that a couple of them weren't young at all; why, that man had to be older than he was, and wearing an emerald-green cloak! The nerve of him! But then it struck Mr. Dursley that this was probably some silly stunt — these people were obviously collecting for something… yes, that would be it. The traffic moved on and a few minutes later, Mr. Dursley arrived in the Grunnings parking lot, his mind back on drills.
Mr. and Mrs. Dursley, of number four, Privet Drive, were proud to say that they were perfectly normal, thank you very much. They were the last people you'd expect to be involved in anything strange or mysterious, because they just didn't hold with such nonsense. Mr. Dursley was the director of a firm called Grunnings, which made drills. He was a big, beefy man with hardly any neck, although he did have a very large mustache. Mrs. Dursley was thin and blonde and had nearly twice the usual amount of neck, which came in very useful as she spent so much of her time craning over garden fences, spying on the neighbors. The Dursleys had a small son called Dudley and in their opinion there was no finer boy anywhere. The Dursleys had everything they wanted, but they also had a secret, and their greatest fear was that somebody would discover it. They didn't think they could bear it if anyone found out about the Potters. Mrs. Potter was Mrs. Dursley's sister, but they hadn't met for several years; in fact, Mrs. Dursley pretended she didn't have a sister, because her sister and her good-for-nothing husband were as unDursleyish as it was possible to be. The Dursleys shuddered to think what the neighbors would say if the Potters arrived in the street. The Dursleys knew that the Potters had a small son, too, but they had never even seen him. This boy was another good reason for keeping the Potters away; they didn't want Dudley mixing with a child like that.When Mr. and Mrs. Dursley woke up on the dull, gray Tuesday our story starts, there was nothing about the cloudy sky outside to suggest that strange and mysterious things would soon be happening all over the country. Mr. Dursley hummed as he picked out his most boring tie for work, and Mrs. Dursley gossiped away happily as she wrestled a screaming Dudley into his high chair. None of them noticed a large, tawny owl flutter past the window. At half past eight, Mr. Dursley picked up his briefcase, pecked Mrs. Dursley on the cheek, and tried to kiss Dudley good-bye but missed, because Dudley was now having a tantrum and throwing his cereal at the walls. “Little tyke,” chortled Mr. Dursley as he left the house. He got into his car and backed out of number four's drive. It was on the corner of the street that he noticed the first sign of something peculiar — a cat reading a map. For a second, Mr. Dursley didn't realize what he had seen — then he jerked his head around to look again. There was a tabby cat standing on the corner of Privet Drive, but there wasn't a map in sight. What could he have been thinking of? It must have been a trick of the light. Mr. Dursley blinked and stared at the cat. It stared back. As Mr. Dursley drove around the corner and up the road, he watched the cat in his mirror. It was now reading the sign that said Privet Drive — no, looking at the sign; cats couldn't read maps or signs. Mr. Dursley gave himself a little shake and put the cat out of his mind. As he drove toward town he thought of nothing except a large order of drills he was hoping to get that day. But on the edge of town, drills were driven out of his mind by something else. As he sat in the usual morning traffic jam, he couldn't help noticing that there seemed to be a lot of strangely dressed people about. People in cloaks. Mr. Dursley couldn't bear people who dressed in funny clothes — the getups you saw on young people! He supposed this was some stupid new fashion. He drummed his fingers on the steering wheel and his eyes fell on a huddle of these weirdos standing quite close by. They were whispering excitedly together. Mr. Dursley was enraged to see that a couple of them weren't young at all; why, that man had to be older than he was, and wearing an emerald-green cloak! The nerve of him! But then it struck Mr. Dursley that this was probably some silly stunt — these people were obviously collecting for something… yes, that would be it. The traffic moved on and a few minutes later, Mr. Dursley arrived in the Grunnings parking lot, his mind back on drills.
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