Add support for deepseek coder v2 lite (#882)

* feat: add support for deepseek-ai/DeepSeek-Coder-V2-Lite-Instruct

* fix softmax + some cleanup

* more nits

* fix rope

* fix original_max_position_embeddings in rope

* fix original_max_position_embeddings in rope config

* add group greedy

---------

Co-authored-by: Awni Hannun <awni@apple.com>
This commit is contained in:
Anchen 2024-07-18 00:23:28 +10:00 committed by GitHub
parent f0c6c6e226
commit 561dcf5643
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2 changed files with 478 additions and 4 deletions

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@ -15,7 +15,12 @@ class KVCache:
def __init__(self, head_dim, n_kv_heads):
self.n_kv_heads = n_kv_heads
self.head_dim = head_dim
if isinstance(head_dim, int):
self.k_head_dim = self.v_head_dim = head_dim
elif isinstance(head_dim, tuple) and len(head_dim) == 2:
self.k_head_dim, self.v_head_dim = head_dim
else:
raise ValueError("head_dim must be an int or a tuple of two ints")
self.keys = None
self.values = None
self.offset = 0
@ -25,9 +30,10 @@ class KVCache:
prev = self.offset
if self.keys is None or (prev + keys.shape[2]) > self.keys.shape[2]:
n_steps = (self.step + keys.shape[2] - 1) // self.step
shape = (1, self.n_kv_heads, n_steps * self.step, self.head_dim)
new_k = mx.zeros(shape, keys.dtype)
new_v = mx.zeros(shape, values.dtype)
k_shape = (1, self.n_kv_heads, n_steps * self.step, self.k_head_dim)
v_shape = (1, self.n_kv_heads, n_steps * self.step, self.v_head_dim)
new_k = mx.zeros(k_shape, keys.dtype)
new_v = mx.zeros(v_shape, values.dtype)
if self.keys is not None:
if prev % self.step != 0:
self.keys = self.keys[..., :prev, :]

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@ -0,0 +1,468 @@
import math
from dataclasses import dataclass
from typing import Dict, Optional, Tuple
import mlx.core as mx
import mlx.nn as nn
from .base import BaseModelArgs, KVCache
from .switch_layers import SwitchGLU
@dataclass
class ModelArgs(BaseModelArgs):
model_type: str = "deepseek_v2"
vocab_size: int = 102400
hidden_size: int = 4096
intermediate_size: int = 11008
moe_intermediate_size: int = 1407
num_hidden_layers: int = 30
num_attention_heads: int = 32
num_key_value_heads: int = 32
n_shared_experts: Optional[int] = None
n_routed_experts: Optional[int] = None
routed_scaling_factor: float = 1.0
kv_lora_rank: int = 512
q_lora_rank: int = 1536
qk_rope_head_dim: int = 64
v_head_dim: int = 128
qk_nope_head_dim: int = 128
topk_method: str = "gready"
n_group: Optional[int] = None
topk_group: Optional[int] = None
num_experts_per_tok: Optional[int] = None
moe_layer_freq: int = 1
first_k_dense_replace: int = 0
max_position_embeddings: int = 2048
rms_norm_eps: float = 1e-6
rope_theta: float = 10000.0
rope_scaling: Optional[Dict] = None
attention_bias: bool = False
def yarn_find_correction_dim(
num_rotations, dim, base=10000, max_position_embeddings=2048
):
return (dim * math.log(max_position_embeddings / (num_rotations * 2 * math.pi))) / (
2 * math.log(base)
)
def yarn_find_correction_range(
low_rot, high_rot, dim, base=10000, max_position_embeddings=2048
):
low = math.floor(
yarn_find_correction_dim(low_rot, dim, base, max_position_embeddings)
)
high = math.ceil(
yarn_find_correction_dim(high_rot, dim, base, max_position_embeddings)
)
return max(low, 0), min(high, dim - 1)
def yarn_get_mscale(scale=1, mscale=1):
if scale <= 1:
return 1.0
return 0.1 * mscale * math.log(scale) + 1.0
def yarn_linear_ramp_mask(min, max, dim):
if min == max:
max += 0.001 # Prevent singularity
linear_func = (mx.arange(dim, dtype=mx.float32) - min) / (max - min)
ramp_func = mx.clip(linear_func, 0, 1)
return ramp_func
class DeepseekV2YarnRotaryEmbedding(nn.Module):
def __init__(
self,
dim,
max_position_embeddings=2048,
base=10000,
scaling_factor=1.0,
original_max_position_embeddings=4096,
beta_fast=32,
beta_slow=1,
mscale=1,
mscale_all_dim=0,
):
super().__init__()
self.dim = dim
self.max_position_embeddings = max_position_embeddings
self.base = base
self.scaling_factor = scaling_factor
self.original_max_position_embeddings = original_max_position_embeddings
self.beta_fast = beta_fast
self.beta_slow = beta_slow
self.mscale = mscale
self.mscale_all_dim = mscale_all_dim
self.max_seq_len_cached = None
self._cos_cached = None
self._sin_cached = None
self._inv_freq = None
self.set_cos_sin_cache(max_position_embeddings)
def set_cos_sin_cache(self, seq_len):
self.max_seq_len_cached = seq_len
dim = self.dim
freq_extra = 1.0 / (self.base ** (mx.arange(0, dim, 2, dtype=mx.float32) / dim))
freq_inter = 1.0 / (
self.scaling_factor
* self.base ** (mx.arange(0, dim, 2, dtype=mx.float32) / dim)
)
low, high = yarn_find_correction_range(
self.beta_fast,
self.beta_slow,
dim,
self.base,
self.original_max_position_embeddings,
)
inv_freq_mask = 1.0 - yarn_linear_ramp_mask(low, high, dim // 2)
inv_freq = freq_inter * (1 - inv_freq_mask) + freq_extra * inv_freq_mask
self._inv_freq = inv_freq
t = mx.arange(seq_len, dtype=mx.float32)
freqs = mx.outer(t, inv_freq)
mscale = yarn_get_mscale(self.scaling_factor, self.mscale) / yarn_get_mscale(
self.scaling_factor, self.mscale_all_dim
)
self._cos_cached = mx.cos(freqs) * mscale
self._sin_cached = mx.sin(freqs) * mscale
def apply_rotary_pos_emb(self, x, cos, sin):
x1 = x[..., ::2]
x2 = x[..., 1::2]
rx1 = x1 * cos - x2 * sin
rx2 = x1 * sin + x2 * cos
return mx.concatenate([rx1, rx2], axis=-1)
def __call__(self, x, offset=0):
seq_len = offset + x.shape[2]
if self.max_seq_len_cached is None or seq_len > self.max_seq_len_cached:
self.set_cos_sin_cache(seq_len=seq_len)
if self._cos_cached.dtype != x.dtype:
self._cos_cached = self._cos_cached.astype(x.dtype)
self._sin_cached = self._sin_cached.astype(x.dtype)
return self.apply_rotary_pos_emb(
x,
self._cos_cached[offset:seq_len],
self._sin_cached[offset:seq_len],
)
class DeepseekV2Attention(nn.Module):
def __init__(self, config: ModelArgs):
super().__init__()
self.config = config
self.hidden_size = config.hidden_size
self.num_heads = config.num_attention_heads
self.max_position_embeddings = config.max_position_embeddings
self.rope_theta = config.rope_theta
self.q_lora_rank = config.q_lora_rank
self.qk_rope_head_dim = config.qk_rope_head_dim
self.kv_lora_rank = config.kv_lora_rank
self.v_head_dim = config.v_head_dim
self.qk_nope_head_dim = config.qk_nope_head_dim
self.q_head_dim = config.qk_nope_head_dim + config.qk_rope_head_dim
self.scale = self.q_head_dim**-0.5
if self.q_lora_rank is None:
self.q_proj = nn.Linear(
self.hidden_size, self.num_heads * self.q_head_dim, bias=False
)
else:
self.q_a_proj = nn.Linear(
self.hidden_size, self.q_lora_rank, bias=config.attention_bias
)
self.q_a_layernorm = nn.RMSNorm(self.q_lora_rank)
self.q_b_proj = nn.Linear(
self.q_lora_rank, self.num_heads * self.q_head_dim, bias=False
)
self.kv_a_proj_with_mqa = nn.Linear(
self.hidden_size,
self.kv_lora_rank + self.qk_rope_head_dim,
bias=config.attention_bias,
)
self.kv_a_layernorm = nn.RMSNorm(self.kv_lora_rank)
self.kv_b_proj = nn.Linear(
self.kv_lora_rank,
self.num_heads
* (self.q_head_dim - self.qk_rope_head_dim + self.v_head_dim),
bias=False,
)
self.o_proj = nn.Linear(
self.num_heads * self.v_head_dim,
self.hidden_size,
bias=config.attention_bias,
)
if self.config.rope_scaling is not None:
mscale_all_dim = self.config.rope_scaling.get("mscale_all_dim", 0)
scaling_factor = self.config.rope_scaling["factor"]
if mscale_all_dim:
mscale = yarn_get_mscale(scaling_factor, mscale_all_dim)
self.scale = self.scale * mscale * mscale
rope_kwargs = {
key: self.config.rope_scaling[key]
for key in [
"original_max_position_embeddings",
"beta_fast",
"beta_slow",
"mscale",
"mscale_all_dim",
]
if key in self.config.rope_scaling
}
self.rope = DeepseekV2YarnRotaryEmbedding(
dim=self.qk_rope_head_dim,
max_position_embeddings=self.max_position_embeddings,
scaling_factor=scaling_factor,
base=self.rope_theta,
**rope_kwargs,
)
def __call__(
self,
x: mx.array,
mask: Optional[mx.array] = None,
cache: Optional[KVCache] = None,
) -> mx.array:
B, L, D = x.shape
if self.q_lora_rank is None:
q = self.q_proj(x)
else:
q = self.q_b_proj(self.q_a_layernorm(self.q_a_proj(x)))
q = q.reshape(B, L, self.num_heads, self.q_head_dim).transpose(0, 2, 1, 3)
q_nope, q_pe = mx.split(q, [self.qk_nope_head_dim], axis=-1)
compressed_kv = self.kv_a_proj_with_mqa(x)
compressed_kv, k_pe = mx.split(compressed_kv, [self.kv_lora_rank], axis=-1)
k_pe = k_pe.reshape(B, L, 1, self.qk_rope_head_dim).transpose(0, 2, 1, 3)
kv = self.kv_b_proj(self.kv_a_layernorm(compressed_kv))
kv = kv.reshape(B, L, self.num_heads, -1).transpose(0, 2, 1, 3)
k_nope, values = mx.split(kv, [self.qk_nope_head_dim], axis=-1)
k_pe = mx.concatenate([k_pe] * self.num_heads, axis=1)
if cache is not None:
q_pe = self.rope(q_pe, cache.offset)
k_pe = self.rope(k_pe, cache.offset)
keys, values = cache.update_and_fetch(
mx.concatenate([k_nope, k_pe], axis=-1), values
)
else:
q_pe = self.rope(q_pe)
k_pe = self.rope(k_pe)
keys = mx.concatenate([k_nope, k_pe], axis=-1)
queries = mx.concatenate([q_nope, q_pe], axis=-1)
output = mx.fast.scaled_dot_product_attention(
queries, keys, values, scale=self.scale, mask=mask
)
output = output.transpose(0, 2, 1, 3).reshape(B, L, -1)
return self.o_proj(output)
class DeepseekV2MLP(nn.Module):
def __init__(
self, config: ModelArgs, hidden_size: int = None, intermediate_size: int = None
):
super().__init__()
self.config = config
self.hidden_size = config.hidden_size if hidden_size is None else hidden_size
self.intermediate_size = (
config.intermediate_size if intermediate_size is None else intermediate_size
)
self.gate_proj = nn.Linear(self.hidden_size, self.intermediate_size, bias=False)
self.up_proj = nn.Linear(self.hidden_size, self.intermediate_size, bias=False)
self.down_proj = nn.Linear(self.intermediate_size, self.hidden_size, bias=False)
def __call__(self, x):
down_proj = self.down_proj(nn.silu(self.gate_proj(x)) * self.up_proj(x))
return down_proj
class MoEGate(nn.Module):
def __init__(self, config: ModelArgs):
super().__init__()
self.config = config
self.top_k = config.num_experts_per_tok
self.n_routed_experts = config.n_routed_experts
self.routed_scaling_factor = config.routed_scaling_factor
self.topk_method = config.topk_method
self.n_group = config.n_group
self.topk_group = config.topk_group
self.weight = mx.zeros((self.n_routed_experts, config.hidden_size))
def __call__(self, x):
gates = x @ self.weight.T
scores = mx.softmax(gates, axis=-1, precise=True)
if self.topk_method == "group_limited_greedy":
bsz, seq_len = x.shape[:2]
scores = scores.reshape(bsz, seq_len, self.n_group, -1)
group_scores = scores.max(axis=-1)
k = self.n_group - self.topk_group
group_idx = mx.argpartition(group_scores, kth=k - 1, axis=-1)[..., :k]
batch_idx = mx.expand_dims(mx.arange(bsz), (1, 2))
seq_idx = mx.expand_dims(mx.arange(seq_len), (0, 2))
scores[batch_idx, seq_idx, group_idx] = 0.0
scores = scores.reshape(bsz, seq_len, -1)
k = self.top_k
inds = mx.stop_gradient(mx.argpartition(-scores, kth=k - 1, axis=-1)[..., :k])
scores = mx.take_along_axis(scores, inds, axis=-1)
scores = scores * self.routed_scaling_factor
return inds, scores
class DeepseekV2MoE(nn.Module):
def __init__(self, config: ModelArgs):
super().__init__()
self.config = config
self.num_experts_per_tok = config.num_experts_per_tok
self.switch_mlp = SwitchGLU(
config.hidden_size, config.moe_intermediate_size, config.n_routed_experts
)
self.gate = MoEGate(config)
if config.n_shared_experts is not None:
intermediate_size = config.moe_intermediate_size * config.n_shared_experts
self.shared_experts = DeepseekV2MLP(
config=config, intermediate_size=intermediate_size
)
def __call__(self, x):
inds, scores = self.gate(x)
y = self.switch_mlp(x, inds)
y = (y * scores[..., None]).sum(axis=-2)
if self.config.n_shared_experts is not None:
y = y + self.shared_experts(x)
return y
class DeepseekV2DecoderLayer(nn.Module):
def __init__(self, config: ModelArgs, layer_idx: int):
super().__init__()
self.self_attn = DeepseekV2Attention(config)
self.mlp = (
DeepseekV2MoE(config)
if (
config.n_routed_experts is not None
and layer_idx >= config.first_k_dense_replace
and layer_idx % config.moe_layer_freq == 0
)
else DeepseekV2MLP(config)
)
self.input_layernorm = nn.RMSNorm(config.hidden_size, eps=config.rms_norm_eps)
self.post_attention_layernorm = nn.RMSNorm(
config.hidden_size, eps=config.rms_norm_eps
)
def __call__(
self,
x: mx.array,
mask: Optional[mx.array] = None,
cache: Optional[KVCache] = None,
) -> mx.array:
r = self.self_attn(self.input_layernorm(x), mask, cache)
h = x + r
r = self.mlp(self.post_attention_layernorm(h))
out = h + r
return out
class DeepseekV2Model(nn.Module):
def __init__(self, config: ModelArgs):
super().__init__()
self.vocab_size = config.vocab_size
self.embed_tokens = nn.Embedding(config.vocab_size, config.hidden_size)
self.layers = [
DeepseekV2DecoderLayer(config, idx)
for idx in range(config.num_hidden_layers)
]
self.norm = nn.RMSNorm(config.hidden_size, eps=config.rms_norm_eps)
def __call__(
self,
x: mx.array,
cache: Optional[KVCache] = None,
) -> mx.array:
h = self.embed_tokens(x)
mask = None
T = h.shape[1]
if T > 1:
mask = nn.MultiHeadAttention.create_additive_causal_mask(T)
mask = mask.astype(h.dtype)
if cache is None:
cache = [None] * len(self.layers)
for layer, c in zip(self.layers, cache):
h = layer(h, mask, c)
return self.norm(h)
class Model(nn.Module):
def __init__(self, config: ModelArgs):
super().__init__()
self.args = config
self.model_type = config.model_type
self.model = DeepseekV2Model(config)
self.lm_head = nn.Linear(config.hidden_size, config.vocab_size, bias=False)
def __call__(
self,
inputs: mx.array,
cache: Optional[KVCache] = None,
):
out = self.model(inputs, cache)
return self.lm_head(out)
def sanitize(self, weights):
for l in range(self.args.num_hidden_layers):
prefix = f"model.layers.{l}"
for n, m in [("w1", "gate_proj"), ("w2", "down_proj"), ("w3", "up_proj")]:
for k in ["weight", "scales", "biases"]:
if f"{prefix}.mlp.experts.0.{m}.{k}" in weights:
to_join = [
weights.pop(f"{prefix}.mlp.experts.{e}.{m}.{k}")
for e in range(self.args.n_routed_experts)
]
weights[f"{prefix}.mlp.switch_mlp.{m}.{k}"] = mx.stack(to_join)
return weights
@property
def layers(self):
return self.model.layers
@property
def head_dim(self):
return (
self.args.qk_nope_head_dim + self.args.qk_rope_head_dim,
self.args.v_head_dim,
)
@property
def n_kv_heads(self):
return self.args.num_key_value_heads