diff --git a/.github/workflows/basic-tests-linux-uv.yml b/.github/workflows/basic-tests-linux-uv.yml index 35864a8..ab651f0 100644 --- a/.github/workflows/basic-tests-linux-uv.yml +++ b/.github/workflows/basic-tests-linux-uv.yml @@ -71,4 +71,5 @@ jobs: shell: bash run: | source .venv/bin/activate + uv pip install transformers pytest pkg/llms_from_scratch/tests/ diff --git a/.github/workflows/check-links.yml b/.github/workflows/check-links.yml index b35e7f1..a5b57e9 100644 --- a/.github/workflows/check-links.yml +++ b/.github/workflows/check-links.yml @@ -24,8 +24,6 @@ jobs: run: | curl -LsSf https://astral.sh/uv/install.sh | sh uv add pytest-ruff pytest-check-links - # Current version of retry doesn't work well if there are broken non-URL links - # pip install pytest pytest-check-links pytest-retry - name: Check links run: | @@ -40,5 +38,3 @@ jobs: --check-links-ignore "https://arxiv.org/*" \ --check-links-ignore "https://ai.stanford.edu/~amaas/data/sentiment/" \ --check-links-ignore "https://x.com/*" - # pytest --check-links ./ --check-links-ignore "https://platform.openai.com/*" --check-links-ignore "https://arena.lmsys.org" --retries 2 --retry-delay 5 - diff --git a/ch05/07_gpt_to_llama/README.md b/ch05/07_gpt_to_llama/README.md index fda7ab7..b158c17 100644 --- a/ch05/07_gpt_to_llama/README.md +++ b/ch05/07_gpt_to_llama/README.md @@ -8,4 +8,188 @@ This folder contains code for converting the GPT implementation from chapter 4 a - [converting-llama2-to-llama3.ipynb](converting-llama2-to-llama3.ipynb): contains code to convert the Llama 2 model to Llama 3, Llama 3.1, and Llama 3.2 - [standalone-llama32.ipynb](standalone-llama32.ipynb): a standalone notebook implementing Llama 3.2 - \ No newline at end of file + + + +  +### Using Llama 3.2 via the `llms-from-scratch` package + +For an easy way to use the Llama 3.2 1B and 3B models, you can also use the `llms-from-scratch` PyPI package based on the source code in this repository at [pkg/llms_from_scratch](../../pkg/llms_from_scratch). + +  +##### 1) Installation + +```bash +pip install llms_from_scratch blobfile +``` +  +##### 2) Model and text generation settings + +Specify which model to use: + +```python +MODEL_FILE = "llama3.2-1B-instruct.pth" +# MODEL_FILE = "llama3.2-1B-base.pth" +# MODEL_FILE = "llama3.2-3B-instruct.pth" +# MODEL_FILE = "llama3.2-3B-base.pth" +``` + +Basic text generation settings that can be defined by the user. Note that the recommended 8192-token context size requires approximately 3 GB of VRAM for the text generation example. + +```python +MODEL_CONTEXT_LENGTH = 8192 # Supports up to 131_072 + +# Text generation settings +if "instruct" in MODEL_FILE: + PROMPT = "What do llamas eat?" +else: + PROMPT = "Llamas eat" + +MAX_NEW_TOKENS = 150 +TEMPERATURE = 0. +TOP_K = 1 +``` + +  +##### 3) Weight download and loading + +This automatically downloads the weight file based on the model choice above: + +```python +import os +import urllib.request + +url = f"https://huggingface.co/rasbt/llama-3.2-from-scratch/resolve/main/{MODEL_FILE}" + +if not os.path.exists(MODEL_FILE): + urllib.request.urlretrieve(url, MODEL_FILE) + print(f"Downloaded to {MODEL_FILE}") +``` + +The model weights are then loaded as follows: + +```python +import torch +from llms_from_scratch.llama3 import Llama3Model + +if "1B" in MODEL_FILE: + from llms_from_scratch.llama3 import LLAMA32_CONFIG_1B as LLAMA32_CONFIG +elif "3B" in MODEL_FILE: + from llms_from_scratch.llama3 import LLAMA32_CONFIG_3B as LLAMA32_CONFIG +else: + raise ValueError("Incorrect model file name") + +LLAMA32_CONFIG["context_length"] = MODEL_CONTEXT_LENGTH + +model = Llama3Model(LLAMA32_CONFIG) +model.load_state_dict(torch.load(MODEL_FILE, weights_only=True)) + +device = ( + torch.device("cuda") if torch.cuda.is_available() else + torch.device("mps") if torch.backends.mps.is_available() else + torch.device("cpu") +) +model.to(device) +``` + +  +##### 4) Initialize tokenizer + +The following code downloads and initializes the tokenizer: + +```python +from llms_from_scratch.llama3 import Llama3Tokenizer, ChatFormat, clean_text + +TOKENIZER_FILE = "tokenizer.model" + +url = f"https://huggingface.co/rasbt/llama-3.2-from-scratch/resolve/main/{TOKENIZER_FILE}" + +if not os.path.exists(TOKENIZER_FILE): + urllib.request.urlretrieve(url, TOKENIZER_FILE) + print(f"Downloaded to {TOKENIZER_FILE}") + +tokenizer = Llama3Tokenizer("tokenizer.model") + +if "instruct" in MODEL_FILE: + tokenizer = ChatFormat(tokenizer) +``` + +  +##### 5) Generating text + +Lastly, we can generate text via the following code: + +```python +import time + +from llms_from_scratch.ch05 import ( + generate, + text_to_token_ids, + token_ids_to_text +) + +torch.manual_seed(123) + +start = time.time() + +token_ids = generate( + model=model, + idx=text_to_token_ids(PROMPT, tokenizer).to(device), + max_new_tokens=MAX_NEW_TOKENS, + context_size=LLAMA32_CONFIG["context_length"], + top_k=TOP_K, + temperature=TEMPERATURE +) + +print(f"Time: {time.time() - start:.2f} sec") + +if torch.cuda.is_available(): + max_mem_bytes = torch.cuda.max_memory_allocated() + max_mem_gb = max_mem_bytes / (1024 ** 3) + print(f"Max memory allocated: {max_mem_gb:.2f} GB") + +output_text = token_ids_to_text(token_ids, tokenizer) + +if "instruct" in MODEL_FILE: + output_text = clean_text(output_text) + +print("\n\nOutput text:\n\n", output_text) +``` + +When using the Llama 3.2 1B Instruct model, the output should look similar to the one shown below: + +``` +Time: 4.12 sec +Max memory allocated: 2.91 GB + + +Output text: + + Llamas are herbivores, which means they primarily eat plants. Their diet consists mainly of: + +1. Grasses: Llamas love to graze on various types of grasses, including tall grasses and grassy meadows. +2. Hay: Llamas also eat hay, which is a dry, compressed form of grass or other plants. +3. Alfalfa: Alfalfa is a legume that is commonly used as a hay substitute in llama feed. +4. Other plants: Llamas will also eat other plants, such as clover, dandelions, and wild grasses. + +It's worth noting that the specific diet of llamas can vary depending on factors such as the breed, +``` + +  +**Pro tip** + +For up to a 4× speed-up, replace + +```python +model.to(device) +``` + +with + +```python +model = torch.compile(model) +model.to(device) +``` + +Note: the speed-up takes effect after the first `generate` call. + diff --git a/pkg/llms_from_scratch/README.md b/pkg/llms_from_scratch/README.md index 355d967..7b2bddd 100644 --- a/pkg/llms_from_scratch/README.md +++ b/pkg/llms_from_scratch/README.md @@ -109,5 +109,13 @@ from llms_from_scratch.ch07 import ( from llms_from_scratch.appendix_a import NeuralNetwork, ToyDataset from llms_from_scratch.appendix_d import find_highest_gradient, train_model + +from llms_from_scratch.llama3 import ( + Llama3Model, + Llama3Tokenizer, + ChatFormat, + clean_text +) ``` +(For the `llms_from_scratch.llama3` usage information, please see [this bonus section](../../ch05/07_gpt_to_llama/README.md). diff --git a/pkg/llms_from_scratch/llama3.py b/pkg/llms_from_scratch/llama3.py new file mode 100644 index 0000000..203b996 --- /dev/null +++ b/pkg/llms_from_scratch/llama3.py @@ -0,0 +1,377 @@ +# Copyright (c) Sebastian Raschka under Apache License 2.0 (see LICENSE.txt). +# Source for "Build a Large Language Model From Scratch" +# - https://www.manning.com/books/build-a-large-language-model-from-scratch +# Code: https://github.com/rasbt/LLMs-from-scratch + +import os +from pathlib import Path + +import torch +import torch.nn as nn + +import tiktoken +from tiktoken.load import load_tiktoken_bpe + + +LLAMA32_CONFIG_1B = { + "vocab_size": 128_256, # Vocabulary size + "context_length": 8192, # Maximum context length to use (reduced to save memory) + "orig_context_length": 131_072, # Context length that was used to train the model + "emb_dim": 2048, # Embedding dimension + "n_heads": 32, # Number of attention heads + "n_layers": 16, # Number of layers + "hidden_dim": 8192, # Size of the intermediate dimension in FeedForward + "n_kv_groups": 8, # Key-Value groups for grouped-query attention + "rope_base": 500_000.0, # The base in RoPE's "theta" + "dtype": torch.bfloat16, # Lower-precision dtype to reduce memory usage + "rope_freq": { # RoPE frequency scaling + "factor": 32.0, + "low_freq_factor": 1.0, + "high_freq_factor": 4.0, + "original_context_length": 8192, + } +} + +LLAMA32_CONFIG_3B = { + "vocab_size": 128_256, # Vocabulary size + "context_length": 8192, # Maximum context length to use (reduced to save memory) + "orig_context_length": 131_072, # Context length that was used to train the model + "emb_dim": 3072, # Embedding dimension + "n_heads": 24, # Number of attention heads + "n_layers": 28, # Number of layers + "hidden_dim": 8192, # Size of the intermediate dimension in FeedForward + "n_kv_groups": 8, # Key-Value groups for grouped-query attention + "rope_base": 500_000.0, # The base in RoPE's "theta" + "dtype": torch.bfloat16, # Lower-precision dtype to reduce memory usage + "rope_freq": { # RoPE frequency scaling + "factor": 32.0, + "low_freq_factor": 1.0, + "high_freq_factor": 4.0, + "original_context_length": 8192, + } +} + + +class Llama3Model(nn.Module): + def __init__(self, cfg): + super().__init__() + + # Main model parameters + self.tok_emb = nn.Embedding(cfg["vocab_size"], cfg["emb_dim"], dtype=cfg["dtype"]) + + self.trf_blocks = nn.ModuleList( # ModuleList since Sequential can only accept one input, and we need `x, mask, cos, sin` + [TransformerBlock(cfg) for _ in range(cfg["n_layers"])] + ) + + self.final_norm = nn.RMSNorm(cfg["emb_dim"], eps=1e-5, dtype=cfg["dtype"]) + self.out_head = nn.Linear(cfg["emb_dim"], cfg["vocab_size"], bias=False, dtype=cfg["dtype"]) + + # Reusuable utilities + self.register_buffer("mask", torch.triu(torch.ones(cfg["context_length"], cfg["context_length"]), diagonal=1).bool()) + + if cfg["orig_context_length"] != cfg["context_length"]: + cfg["rope_base"] = rescale_theta( + cfg["rope_base"], + cfg["orig_context_length"], + cfg["context_length"] + ) + cos, sin = compute_rope_params( + head_dim=cfg["emb_dim"] // cfg["n_heads"], + theta_base=cfg["rope_base"], + context_length=cfg["context_length"], + freq_config=cfg["rope_freq"] + ) + self.register_buffer("cos", cos, persistent=False) + self.register_buffer("sin", sin, persistent=False) + self.cfg = cfg + + def forward(self, in_idx): + # Forward pass + tok_embeds = self.tok_emb(in_idx) + x = tok_embeds + + for block in self.trf_blocks: + x = block(x, self.mask, self.cos, self.sin) + x = self.final_norm(x) + logits = self.out_head(x.to(self.cfg["dtype"])) + return logits + + +class TransformerBlock(nn.Module): + def __init__(self, cfg): + super().__init__() + self.att = GroupedQueryAttention( + d_in=cfg["emb_dim"], + d_out=cfg["emb_dim"], + num_heads=cfg["n_heads"], + num_kv_groups=cfg["n_kv_groups"], + dtype=cfg["dtype"] + ) + self.ff = FeedForward(cfg) + self.norm1 = nn.RMSNorm(cfg["emb_dim"], eps=1e-5, dtype=cfg["dtype"]) + self.norm2 = nn.RMSNorm(cfg["emb_dim"], eps=1e-5, dtype=cfg["dtype"]) + + def forward(self, x, mask, cos, sin): + # Shortcut connection for attention block + shortcut = x + x = self.norm1(x) + x = self.att(x, mask, cos, sin) # Shape [batch_size, num_tokens, emb_size] + x = x + shortcut # Add the original input back + + # Shortcut connection for feed-forward block + shortcut = x + x = self.norm2(x) + x = self.ff(x) + x = x + shortcut # Add the original input back + + return x + + +class FeedForward(nn.Module): + def __init__(self, cfg): + super().__init__() + self.fc1 = nn.Linear(cfg["emb_dim"], cfg["hidden_dim"], dtype=cfg["dtype"], bias=False) + self.fc2 = nn.Linear(cfg["emb_dim"], cfg["hidden_dim"], dtype=cfg["dtype"], bias=False) + self.fc3 = nn.Linear(cfg["hidden_dim"], cfg["emb_dim"], dtype=cfg["dtype"], bias=False) + + def forward(self, x): + x_fc1 = self.fc1(x) + x_fc2 = self.fc2(x) + x = nn.functional.silu(x_fc1) * x_fc2 + return self.fc3(x) + + +class GroupedQueryAttention(nn.Module): + def __init__( + self, d_in, d_out, num_heads, + num_kv_groups, + dtype=None + ): + super().__init__() + assert d_out % num_heads == 0, "d_out must be divisible by num_heads" + assert num_heads % num_kv_groups == 0, "num_heads must be divisible by num_kv_groups" + + self.d_out = d_out + self.num_heads = num_heads + self.head_dim = d_out // num_heads + + self.W_key = nn.Linear(d_in, num_kv_groups * self.head_dim, bias=False, dtype=dtype) + self.W_value = nn.Linear(d_in, num_kv_groups * self.head_dim, bias=False, dtype=dtype) + self.num_kv_groups = num_kv_groups + self.group_size = num_heads // num_kv_groups + + self.W_query = nn.Linear(d_in, d_out, bias=False, dtype=dtype) + self.out_proj = nn.Linear(d_out, d_out, bias=False, dtype=dtype) + + def forward(self, x, mask, cos, sin): + b, num_tokens, d_in = x.shape + + queries = self.W_query(x) # Shape: (b, num_tokens, d_out) + keys = self.W_key(x) # Shape: (b, num_tokens, num_kv_groups * head_dim) + values = self.W_value(x) # Shape: (b, num_tokens, num_kv_groups * head_dim) + + # Reshape queries, keys, and values + queries = queries.view(b, num_tokens, self.num_heads, self.head_dim) + keys = keys.view(b, num_tokens, self.num_kv_groups, self.head_dim) + values = values.view(b, num_tokens, self.num_kv_groups, self.head_dim) + + # Transpose keys, values, and queries + keys = keys.transpose(1, 2) # Shape: (b, num_heads, num_tokens, head_dim) + values = values.transpose(1, 2) # Shape: (b, num_heads, num_tokens, head_dim) + queries = queries.transpose(1, 2) # Shape: (b, num_query_groups, num_tokens, head_dim) + + # Apply RoPE + keys = apply_rope(keys, cos, sin) + queries = apply_rope(queries, cos, sin) + + # Expand keys and values to match the number of heads + # Shape: (b, num_heads, num_tokens, head_dim) + keys = keys.repeat_interleave(self.group_size, dim=1) # Shape: (b, num_heads, num_tokens, head_dim) + values = values.repeat_interleave(self.group_size, dim=1) # Shape: (b, num_heads, num_tokens, head_dim) + # For example, before repeat_interleave along dim=1 (query groups): + # [K1, K2] + # After repeat_interleave (each query group is repeated group_size times): + # [K1, K1, K2, K2] + # If we used regular repeat instead of repeat_interleave, we'd get: + # [K1, K2, K1, K2] + + # Compute scaled dot-product attention (aka self-attention) with a causal mask + # Shape: (b, num_heads, num_tokens, num_tokens) + attn_scores = queries @ keys.transpose(2, 3) # Dot product for each head + + # Use the mask to fill attention scores + attn_scores = attn_scores.masked_fill(mask[:num_tokens, :num_tokens], -torch.inf) + + attn_weights = torch.softmax(attn_scores / keys.shape[-1]**0.5, dim=-1) + assert keys.shape[-1] == self.head_dim + + # Shape: (b, num_tokens, num_heads, head_dim) + context_vec = (attn_weights @ values).transpose(1, 2) + + # Combine heads, where self.d_out = self.num_heads * self.head_dim + context_vec = context_vec.reshape(b, num_tokens, self.d_out) + context_vec = self.out_proj(context_vec) # optional projection + + return context_vec + + +def compute_rope_params(head_dim, theta_base=10_000, context_length=4096, freq_config=None, dtype=torch.float32): + assert head_dim % 2 == 0, "Embedding dimension must be even" + + # Compute the inverse frequencies + inv_freq = 1.0 / (theta_base ** (torch.arange(0, head_dim, 2, dtype=dtype)[: (head_dim // 2)].float() / head_dim)) + + # Frequency adjustments + if freq_config is not None: + low_freq_wavelen = freq_config["original_context_length"] / freq_config["low_freq_factor"] + high_freq_wavelen = freq_config["original_context_length"] / freq_config["high_freq_factor"] + + wavelen = 2 * torch.pi / inv_freq + + inv_freq_llama = torch.where( + wavelen > low_freq_wavelen, inv_freq / freq_config["factor"], inv_freq + ) + + smooth_factor = (freq_config["original_context_length"] / wavelen - freq_config["low_freq_factor"]) / ( + freq_config["high_freq_factor"] - freq_config["low_freq_factor"] + ) + + smoothed_inv_freq = ( + (1 - smooth_factor) * (inv_freq / freq_config["factor"]) + smooth_factor * inv_freq + ) + + is_medium_freq = (wavelen <= low_freq_wavelen) & (wavelen >= high_freq_wavelen) + inv_freq_llama = torch.where(is_medium_freq, smoothed_inv_freq, inv_freq_llama) + inv_freq = inv_freq_llama + + # Generate position indices + positions = torch.arange(context_length, dtype=dtype) + + # Compute the angles + angles = positions[:, None] * inv_freq[None, :] # Shape: (context_length, head_dim // 2) + + # Expand angles to match the head_dim + angles = torch.cat([angles, angles], dim=1) # Shape: (context_length, head_dim) + + # Precompute sine and cosine + cos = torch.cos(angles) + sin = torch.sin(angles) + + return cos, sin + + +def apply_rope(x, cos, sin): + # x: (batch_size, num_heads, seq_len, head_dim) + batch_size, num_heads, seq_len, head_dim = x.shape + assert head_dim % 2 == 0, "Head dimension must be even" + + # Split x into first half and second half + x1 = x[..., : head_dim // 2] # First half + x2 = x[..., head_dim // 2:] # Second half + + # Adjust sin and cos shapes + cos = cos[:seq_len, :].unsqueeze(0).unsqueeze(0) # Shape: (1, 1, seq_len, head_dim) + sin = sin[:seq_len, :].unsqueeze(0).unsqueeze(0) + + # Apply the rotary transformation + rotated = torch.cat((-x2, x1), dim=-1) + x_rotated = (x * cos) + (rotated * sin) + + # It's ok to use lower-precision after applying cos and sin rotation + return x_rotated.to(dtype=x.dtype) + + +def rescale_theta(theta_old, context_length_old, context_length_new): + scaling_factor = context_length_new / context_length_old + theta_new = theta_old * scaling_factor + return theta_new + + +########################################## +# Tokenizer +########################################## + + +class Llama3Tokenizer: + def __init__(self, model_path): + assert os.path.isfile(model_path), f"Model file {model_path} not found" + mergeable_ranks = load_tiktoken_bpe(model_path) + + self.special_tokens = { + "<|begin_of_text|>": 128000, + "<|end_of_text|>": 128001, + "<|start_header_id|>": 128006, + "<|end_header_id|>": 128007, + "<|eot_id|>": 128009, + } + self.special_tokens.update({ + f"<|reserved_{i}|>": 128002 + i for i in range(256) if (128002 + i) not in self.special_tokens.values() + }) + + self.model = tiktoken.Encoding( + name=Path(model_path).name, + pat_str=r"(?i:'s|'t|'re|'ve|'m|'ll|'d)|[^\r\n\p{L}\p{N}]?\p{L}+|\p{N}{1,3}| ?[^\s\p{L}\p{N}]+[\r\n]*|\s*[\r\n]+|\s+(?!\S)|\s+", + mergeable_ranks=mergeable_ranks, + special_tokens=self.special_tokens + ) + + def encode(self, text, bos=False, eos=False, allowed_special=set(), disallowed_special=()): + if bos: + tokens = [self.special_tokens["<|begin_of_text|>"]] + else: + tokens = [] + + tokens += self.model.encode(text, allowed_special=allowed_special, disallowed_special=disallowed_special) + + if eos: + tokens.append(self.special_tokens["<|end_of_text|>"]) + return tokens + + def decode(self, tokens): + return self.model.decode(tokens) + + +class ChatFormat: + def __init__(self, tokenizer): + self.tokenizer = tokenizer + + def encode_header(self, message): + tokens = [] + tokens.append(self.tokenizer.special_tokens["<|start_header_id|>"]) + tokens.extend(self.tokenizer.encode(message["role"], bos=False, eos=False)) + tokens.append(self.tokenizer.special_tokens["<|end_header_id|>"]) + tokens.extend(self.tokenizer.encode("\n\n", bos=False, eos=False)) + return tokens + + def encode(self, text, allowed_special=None): + message = { + "role": "user", + "content": text + } + + tokens = self.encode_header(message) + tokens.extend( + self.tokenizer.encode( + message["content"].strip(), + bos=False, + eos=False, + allowed_special=allowed_special + ) + ) + tokens.append(self.tokenizer.special_tokens["<|eot_id|>"]) + return tokens + + def decode(self, token_ids): + return self.tokenizer.decode(token_ids) + + +def clean_text(text, header_end="assistant<|end_header_id|>\n\n"): + # Find the index of the first occurrence of "<|end_header_id|>" + index = text.find(header_end) + + if index != -1: + # Return the substring starting after "<|end_header_id|>" + return text[index + len(header_end):].strip() # Strip removes leading/trailing whitespace + else: + # If the token is not found, return the original text + return text diff --git a/pkg/llms_from_scratch/tests/test_llama3.py b/pkg/llms_from_scratch/tests/test_llama3.py new file mode 100644 index 0000000..70ff8f5 --- /dev/null +++ b/pkg/llms_from_scratch/tests/test_llama3.py @@ -0,0 +1,147 @@ +# Copyright (c) Sebastian Raschka under Apache License 2.0 (see LICENSE.txt). +# Source for "Build a Large Language Model From Scratch" +# - https://www.manning.com/books/build-a-large-language-model-from-scratch +# Code: https://github.com/rasbt/LLMs-from-scratch + +from llms_from_scratch.ch04 import generate_text_simple +from llms_from_scratch.llama3 import ( + compute_rope_params, + apply_rope, + rescale_theta, + LLAMA32_CONFIG_1B, + Llama3Model +) + +import importlib +import pytest +import tiktoken +import torch + + +transformers_installed = importlib.util.find_spec("transformers") is not None + + +@pytest.mark.skipif(not transformers_installed, reason="transformers not installed") +def test_rope(): + + from transformers.models.llama.modeling_llama import LlamaRotaryEmbedding, apply_rotary_pos_emb + + # Settings + batch_size = 1 + context_len = 8192 + num_heads = 4 + head_dim = 16 + rope_theta = 500_000 + + rope_config = { + "factor": 8.0, + "low_freq_factor": 1.0, + "high_freq_factor": 4.0, + "original_context_length": 8192, + } + + # Instantiate RoPE parameters + cos, sin = compute_rope_params( + head_dim=head_dim, + theta_base=rope_theta, + context_length=context_len, + freq_config=rope_config, + ) + + # Dummy query and key tensors + torch.manual_seed(123) + queries = torch.randn(batch_size, num_heads, context_len, head_dim) + keys = torch.randn(batch_size, num_heads, context_len, head_dim) + + # Apply rotary position embeddings + queries_rot = apply_rope(queries, cos, sin) + keys_rot = apply_rope(keys, cos, sin) + + # Generate reference RoPE via HF + hf_rope_params = { + "factor": 8.0, + "low_freq_factor": 1.0, + "high_freq_factor": 4.0, + "original_max_position_embeddings": 8192, + "rope_type": "llama3" + } + + class RoPEConfig: + rope_type = "llama3" + rope_scaling = hf_rope_params + factor = 1.0 + dim: int = head_dim + rope_theta = 500_000 + max_position_embeddings: int = 8192 + hidden_size = head_dim * num_heads + num_attention_heads = num_heads + + config = RoPEConfig() + + rot_emb = LlamaRotaryEmbedding(config=config) + position_ids = torch.arange(context_len, dtype=torch.long).unsqueeze(0) + ref_cos, ref_sin = rot_emb(queries, position_ids) + ref_queries_rot, ref_keys_rot = apply_rotary_pos_emb(queries, keys, ref_cos, ref_sin) + + torch.testing.assert_close(sin, ref_sin.squeeze(0)) + torch.testing.assert_close(cos, ref_cos.squeeze(0)) + torch.testing.assert_close(keys_rot, ref_keys_rot) + torch.testing.assert_close(queries_rot, ref_queries_rot) + + +GPT_CONFIG_124M = { + "vocab_size": 50257, # Vocabulary size + "context_length": 1024, # Context length + "emb_dim": 768, # Embedding dimension + "n_heads": 12, # Number of attention heads + "n_layers": 12, # Number of layers + "drop_rate": 0.1, # Dropout rate + "qkv_bias": False # Query-Key-Value bias +} + + +def test_rescale(): + + new_theta = rescale_theta( + theta_old=500_000., + context_length_old=131_072, + context_length_new=8192 + ) + assert new_theta == 31250. + + old_theta = rescale_theta( + theta_old=new_theta, + context_length_old=8192, + context_length_new=131_072 + ) + assert old_theta == 500_000. + + +@pytest.mark.parametrize("ModelClass", [Llama3Model]) +def test_gpt_model_variants(ModelClass): + torch.manual_seed(123) + model = ModelClass(LLAMA32_CONFIG_1B) + model.eval() + + start_context = "Hello, I am" + + tokenizer = tiktoken.get_encoding("gpt2") + encoded = tokenizer.encode(start_context) + encoded_tensor = torch.tensor(encoded).unsqueeze(0) + + print(f"\n{50*'='}\n{22*' '}IN\n{50*'='}") + print("\nInput text:", start_context) + print("Encoded input text:", encoded) + print("encoded_tensor.shape:", encoded_tensor.shape) + + out = generate_text_simple( + model=model, + idx=encoded_tensor, + max_new_tokens=10, + context_size=LLAMA32_CONFIG_1B["context_length"] + ) + expect = torch.tensor([ + [15496, 11, 314, 716, 78563, 89362, 19616, 115725, 114917, + 97198, 60342, 19108, 100752, 98969] + ]) + assert torch.equal(expect, out) diff --git a/pyproject.toml b/pyproject.toml index d1bda8f..f0805c0 100644 --- a/pyproject.toml +++ b/pyproject.toml @@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta" [project] name = "llms-from-scratch" -version = "1.0.2" +version = "1.0.5" description = "Implement a ChatGPT-like LLM in PyTorch from scratch, step by step" readme = "README.md" requires-python = ">=3.10"