Files
LEANN/packages/leann-core/src/leann/embedding_compute.py
2025-08-22 14:29:36 -07:00

927 lines
35 KiB
Python

"""
Unified embedding computation module
Consolidates all embedding computation logic using SentenceTransformer
Preserves all optimization parameters to ensure performance
"""
import logging
import os
import time
from typing import Any
import numpy as np
import torch
# Set up logger with proper level
logger = logging.getLogger(__name__)
LOG_LEVEL = os.getenv("LEANN_LOG_LEVEL", "WARNING").upper()
log_level = getattr(logging, LOG_LEVEL, logging.WARNING)
logger.setLevel(log_level)
# Global model cache to avoid repeated loading
_model_cache: dict[str, Any] = {}
# Enable fast tokenizer multithreading by default
os.environ.setdefault("TOKENIZERS_PARALLELISM", "true")
def compute_embeddings(
texts: list[str],
model_name: str,
mode: str = "sentence-transformers",
is_build: bool = False,
batch_size: int = 32,
adaptive_optimization: bool = True,
manual_tokenize: bool = False,
max_length: int = 256,
) -> np.ndarray:
"""
Unified embedding computation entry point
Args:
texts: List of texts to compute embeddings for
model_name: Model name
mode: Computation mode ('sentence-transformers', 'openai', 'mlx', 'ollama')
is_build: Whether this is a build operation (shows progress bar)
batch_size: Batch size for processing
adaptive_optimization: Whether to use adaptive optimization based on batch size
Returns:
Normalized embeddings array, shape: (len(texts), embedding_dim)
"""
if mode == "sentence-transformers":
return compute_embeddings_sentence_transformers(
texts,
model_name,
is_build=is_build,
batch_size=batch_size,
adaptive_optimization=adaptive_optimization,
manual_tokenize=manual_tokenize,
max_length=max_length,
)
elif mode == "openai":
return compute_embeddings_openai(texts, model_name)
elif mode == "mlx":
return compute_embeddings_mlx(texts, model_name)
elif mode == "ollama":
return compute_embeddings_ollama(texts, model_name, is_build=is_build)
elif mode == "gemini":
return compute_embeddings_gemini(texts, model_name, is_build=is_build)
else:
raise ValueError(f"Unsupported embedding mode: {mode}")
def compute_embeddings_sentence_transformers(
texts: list[str],
model_name: str,
use_fp16: bool = True,
device: str = "auto",
batch_size: int = 32,
is_build: bool = False,
adaptive_optimization: bool = True,
manual_tokenize: bool = False,
max_length: int = 256,
) -> np.ndarray:
manual_tokenize = False
batch_size = 512
"""
Compute embeddings using SentenceTransformer with model caching and adaptive optimization
Args:
texts: List of texts to compute embeddings for
model_name: Model name
use_fp16: Whether to use FP16 precision
device: Device to use ('auto', 'cuda', 'mps', 'cpu')
batch_size: Batch size for processing
is_build: Whether this is a build operation (shows progress bar)
adaptive_optimization: Whether to use adaptive optimization based on batch size
"""
# Handle empty input
if not texts:
raise ValueError("Cannot compute embeddings for empty text list")
logger.info(
f"Computing embeddings for {len(texts)} texts using SentenceTransformer, model: '{model_name}'"
)
# Auto-detect device
if device == "auto":
if torch.cuda.is_available():
device = "cuda"
elif hasattr(torch.backends, "mps") and torch.backends.mps.is_available():
device = "mps"
else:
device = "cpu"
# Apply optimizations based on benchmark results
if adaptive_optimization:
# Use optimal batch_size constants for different devices based on benchmark results
if device == "mps":
batch_size = 128 # MPS optimal batch size from benchmark
if model_name == "Qwen/Qwen3-Embedding-0.6B":
batch_size = 32
elif device == "cuda":
batch_size = 256 # CUDA optimal batch size
# Keep original batch_size for CPU
# Create cache key
cache_key = f"sentence_transformers_{model_name}_{device}_{use_fp16}_optimized_len{max_length}"
# Check if model is already cached
if cache_key in _model_cache:
logger.info(f"Using cached optimized model: {model_name}")
model = _model_cache[cache_key]
else:
logger.info(f"Loading and caching optimized SentenceTransformer model: {model_name}")
from sentence_transformers import SentenceTransformer
logger.info(f"Using device: {device}")
# Apply hardware optimizations
if device == "cuda":
# TODO: Haven't tested this yet
torch.backends.cuda.matmul.allow_tf32 = True
torch.backends.cudnn.allow_tf32 = True
torch.backends.cudnn.benchmark = True
torch.backends.cudnn.deterministic = False
torch.cuda.set_per_process_memory_fraction(0.9)
elif device == "mps":
try:
if hasattr(torch.mps, "set_per_process_memory_fraction"):
torch.mps.set_per_process_memory_fraction(0.9)
except AttributeError:
logger.warning("Some MPS optimizations not available in this PyTorch version")
elif device == "cpu":
# TODO: Haven't tested this yet
torch.set_num_threads(min(8, os.cpu_count() or 4))
try:
torch.backends.mkldnn.enabled = True
except AttributeError:
pass
# Prepare optimized model and tokenizer parameters
model_kwargs = {
"torch_dtype": torch.float16 if use_fp16 else torch.float32,
"low_cpu_mem_usage": True,
"_fast_init": True,
}
# Prefer SDPA on CUDA; fall back to eager elsewhere
if device == "cuda":
model_kwargs["attn_implementation"] = "sdpa"
else:
model_kwargs["attn_implementation"] = "eager"
tokenizer_kwargs = {
"use_fast": True,
"padding": "max_length",
"truncation": True,
"max_length": max_length,
}
try:
# Try local loading first
model_kwargs["local_files_only"] = True
tokenizer_kwargs["local_files_only"] = True
model = SentenceTransformer(
model_name,
device=device,
model_kwargs=model_kwargs,
tokenizer_kwargs=tokenizer_kwargs,
local_files_only=True,
)
logger.info("Model loaded successfully! (local + optimized)")
except Exception as e:
logger.warning(f"Local loading failed ({e}), trying network download...")
# Fallback to network loading
model_kwargs["local_files_only"] = False
tokenizer_kwargs["local_files_only"] = False
model = SentenceTransformer(
model_name,
device=device,
model_kwargs=model_kwargs,
tokenizer_kwargs=tokenizer_kwargs,
local_files_only=False,
)
logger.info("Model loaded successfully! (network + optimized)")
# Apply additional optimizations based on mode
if use_fp16 and device in ["cuda", "mps"]:
try:
model = model.half()
logger.info(f"Applied FP16 precision: {model_name}")
except Exception as e:
logger.warning(f"FP16 optimization failed: {e}")
# Apply torch.compile optimization
if device in ["cuda", "mps"]:
try:
model = torch.compile(model, mode="reduce-overhead", dynamic=True)
logger.info(f"Applied torch.compile optimization: {model_name}")
except Exception as e:
logger.warning(f"torch.compile optimization failed: {e}")
# Set model to eval mode and disable gradients for inference
model.eval()
for param in model.parameters():
param.requires_grad_(False)
# Enforce max sequence length for encode path
try:
if hasattr(model, "max_seq_length"):
model.max_seq_length = max_length
except Exception:
pass
# Cache the model
_model_cache[cache_key] = model
logger.info(f"Model cached: {cache_key}")
# Compute embeddings with optimized inference mode
logger.info(
f"Starting embedding computation... (batch_size: {batch_size}, manual_tokenize={manual_tokenize})"
)
start_time = time.time()
if not manual_tokenize:
# Use SentenceTransformer's optimized encode path (default)
# print text shapr
with torch.inference_mode():
# print avg len of texts
avg_len = sum(len(text) for text in texts) / len(texts)
logger.info(f"Avg len of texts: {avg_len}")
# print the precision of the model
logger.info(f"Model precision: {model.dtype}")
time_start = time.time()
embeddings = model.encode(
texts,
batch_size=batch_size,
show_progress_bar=is_build, # Don't show progress bar in server environment
convert_to_tensor=True,
normalize_embeddings=False,
device=device,
max_length=max_length,
)
# Synchronize if CUDA to measure accurate wall time
try:
# if torch.cuda.is_available():
# torch.cuda.synchronize()
time_end = time.time()
embedding_time, embedding_tpt = (
time_end - time_start,
embeddings.shape[0] / (time_end - time_start),
)
logger.info(
f"Time taken in embedding {batch_size} texts in embedding model: {embedding_time} seconds, embedding tpt: {embedding_tpt} seqs/s"
)
except Exception:
pass
# Single CPU copy after timing (avoid per-batch D2H sync)
if isinstance(embeddings, torch.Tensor):
embeddings = embeddings.float().cpu().numpy()
else:
time_start = time.time()
# Manual tokenization + forward pass using HF AutoTokenizer/AutoModel
try:
from transformers import AutoModel, AutoTokenizer # type: ignore
except Exception as e:
raise ImportError(f"transformers is required for manual_tokenize=True: {e}")
# Cache tokenizer and model
tok_cache_key = f"hf_tokenizer_{model_name}_len{max_length}_padmax"
mdl_cache_key = f"hf_model_{model_name}_{device}_{use_fp16}_len{max_length}"
if tok_cache_key in _model_cache and mdl_cache_key in _model_cache:
hf_tokenizer = _model_cache[tok_cache_key]
hf_model = _model_cache[mdl_cache_key]
logger.info("Using cached HF tokenizer/model for manual path")
else:
logger.info("Loading HF tokenizer/model for manual tokenization path")
hf_tokenizer = AutoTokenizer.from_pretrained(model_name, use_fast=True)
torch_dtype = torch.float16 if (use_fp16 and device == "cuda") else torch.float32
hf_model = AutoModel.from_pretrained(model_name, torch_dtype=torch_dtype)
hf_model.to(device)
hf_model.eval()
# Optional compile on supported devices
if device in ["cuda", "mps"]:
try:
hf_model = torch.compile(hf_model, mode="reduce-overhead", dynamic=True) # type: ignore
except Exception:
pass
_model_cache[tok_cache_key] = hf_tokenizer
_model_cache[mdl_cache_key] = hf_model
emb_list: list[torch.Tensor] = []
# Progress bar when building or for large inputs
show_progress = is_build or len(texts) > 32
show_progress = False
try:
if show_progress:
from tqdm import tqdm # type: ignore
batch_iter = tqdm(
range(0, len(texts), batch_size),
desc="Embedding (manual)",
unit="batch",
)
else:
batch_iter = range(0, len(texts), batch_size)
except Exception:
batch_iter = range(0, len(texts), batch_size)
start_time_manual = time.time()
with torch.inference_mode():
for start_index in batch_iter:
end_index = min(start_index + batch_size, len(texts))
batch_texts = texts[start_index:end_index]
tokenize_start_time = time.time()
inputs = hf_tokenizer(
batch_texts,
padding="max_length",
truncation=True,
max_length=max_length,
return_tensors="pt",
)
tokenize_end_time = time.time()
logger.debug(
f"Tokenize time taken: {tokenize_end_time - tokenize_start_time} seconds"
)
to_device_start_time = time.time()
# Pin CPU memory then transfer non-blocking to GPU when available
inputs = {
k: (v.pin_memory() if (device == "cuda" and v.device.type == "cpu") else v)
for k, v in inputs.items()
}
inputs = {
k: v.to(device, non_blocking=(device == "cuda")) for k, v in inputs.items()
}
to_device_end_time = time.time()
logger.debug(
f"To device time taken: {to_device_end_time - to_device_start_time} seconds"
)
# if device == "cuda":
# torch.cuda.synchronize()
forward_start_time = time.time()
outputs = hf_model(**inputs)
# if device == "cuda":
# torch.cuda.synchronize()
forward_end_time = time.time()
logger.debug(f"Forward time taken: {forward_end_time - forward_start_time} seconds")
last_hidden_state = outputs.last_hidden_state # (B, L, H)
attention_mask = inputs.get("attention_mask")
if attention_mask is None:
# Fallback: assume all tokens are valid
pooled = last_hidden_state.mean(dim=1)
else:
mask = attention_mask.unsqueeze(-1).to(last_hidden_state.dtype)
masked = last_hidden_state * mask
lengths = mask.sum(dim=1).clamp(min=1)
pooled = masked.sum(dim=1) / lengths
# Accumulate on-device; single D2H copy after loop
emb_list.append(pooled.detach())
# Concatenate and single-copy to CPU/NumPy
embeddings_tensor = torch.cat(emb_list, dim=0)
embeddings = embeddings_tensor.float().cpu().numpy()
# try:
# if torch.cuda.is_available():
# torch.cuda.synchronize()
# except Exception:
# pass
end_time = time.time()
logger.info(f"Manual tokenize time taken: {end_time - start_time_manual} seconds")
time_end = time.time()
tokenize_time, tokenize_tpt = (
time_end - time_start,
embeddings.shape[0] / (time_end - time_start),
)
logger.info(
f"Tokenize time taken: {tokenize_time} seconds, tokenize tpt: {tokenize_tpt} seqs/s"
)
end_time = time.time()
logger.info(f"Generated {len(embeddings)} embeddings, dimension: {embeddings.shape[1]}")
logger.info(f"Time taken: {end_time - start_time} seconds")
# Validate results
if np.isnan(embeddings).any() or np.isinf(embeddings).any():
raise RuntimeError(f"Detected NaN or Inf values in embeddings, model: {model_name}")
return embeddings
def compute_embeddings_openai(texts: list[str], model_name: str) -> np.ndarray:
# TODO: @yichuan-w add progress bar only in build mode
"""Compute embeddings using OpenAI API"""
try:
import os
import openai
except ImportError as e:
raise ImportError(f"OpenAI package not installed: {e}")
# Validate input list
if not texts:
raise ValueError("Cannot compute embeddings for empty text list")
# Extra validation: abort early if any item is empty/whitespace
invalid_count = sum(1 for t in texts if not isinstance(t, str) or not t.strip())
if invalid_count > 0:
raise ValueError(
f"Found {invalid_count} empty/invalid text(s) in input. Upstream should filter before calling OpenAI."
)
api_key = os.getenv("OPENAI_API_KEY")
if not api_key:
raise RuntimeError("OPENAI_API_KEY environment variable not set")
# Cache OpenAI client
cache_key = "openai_client"
if cache_key in _model_cache:
client = _model_cache[cache_key]
else:
client = openai.OpenAI(api_key=api_key)
_model_cache[cache_key] = client
logger.info("OpenAI client cached")
logger.info(
f"Computing embeddings for {len(texts)} texts using OpenAI API, model: '{model_name}'"
)
print(f"len of texts: {len(texts)}")
# OpenAI has limits on batch size and input length
max_batch_size = 800 # Conservative batch size because the token limit is 300K
all_embeddings = []
# get the avg len of texts
avg_len = sum(len(text) for text in texts) / len(texts)
print(f"avg len of texts: {avg_len}")
# if avg len is less than 1000, use the max batch size
if avg_len > 300:
max_batch_size = 500
# if avg len is less than 1000, use the max batch size
try:
from tqdm import tqdm
total_batches = (len(texts) + max_batch_size - 1) // max_batch_size
batch_range = range(0, len(texts), max_batch_size)
batch_iterator = tqdm(
batch_range, desc="Computing embeddings", unit="batch", total=total_batches
)
except ImportError:
# Fallback when tqdm is not available
batch_iterator = range(0, len(texts), max_batch_size)
for i in batch_iterator:
batch_texts = texts[i : i + max_batch_size]
try:
response = client.embeddings.create(model=model_name, input=batch_texts)
batch_embeddings = [embedding.embedding for embedding in response.data]
all_embeddings.extend(batch_embeddings)
except Exception as e:
logger.error(f"Batch {i} failed: {e}")
raise
embeddings = np.array(all_embeddings, dtype=np.float32)
logger.info(f"Generated {len(embeddings)} embeddings, dimension: {embeddings.shape[1]}")
print(f"len of embeddings: {len(embeddings)}")
return embeddings
def compute_embeddings_mlx(chunks: list[str], model_name: str, batch_size: int = 16) -> np.ndarray:
# TODO: @yichuan-w add progress bar only in build mode
"""Computes embeddings using an MLX model."""
try:
import mlx.core as mx
from mlx_lm.utils import load
except ImportError as e:
raise RuntimeError(
"MLX or related libraries not available. Install with: uv pip install mlx mlx-lm"
) from e
logger.info(
f"Computing embeddings for {len(chunks)} chunks using MLX model '{model_name}' with batch_size={batch_size}..."
)
# Cache MLX model and tokenizer
cache_key = f"mlx_{model_name}"
if cache_key in _model_cache:
logger.info(f"Using cached MLX model: {model_name}")
model, tokenizer = _model_cache[cache_key]
else:
logger.info(f"Loading and caching MLX model: {model_name}")
model, tokenizer = load(model_name)
_model_cache[cache_key] = (model, tokenizer)
logger.info(f"MLX model cached: {cache_key}")
# Process chunks in batches with progress bar
all_embeddings = []
try:
from tqdm import tqdm
batch_iterator = tqdm(
range(0, len(chunks), batch_size), desc="Computing embeddings", unit="batch"
)
except ImportError:
batch_iterator = range(0, len(chunks), batch_size)
for i in batch_iterator:
batch_chunks = chunks[i : i + batch_size]
# Tokenize all chunks in the batch
batch_token_ids = []
for chunk in batch_chunks:
token_ids = tokenizer.encode(chunk) # type: ignore
batch_token_ids.append(token_ids)
# Pad sequences to the same length for batch processing
max_length = max(len(ids) for ids in batch_token_ids)
padded_token_ids = []
for token_ids in batch_token_ids:
# Pad with tokenizer.pad_token_id or 0
padded = token_ids + [0] * (max_length - len(token_ids))
padded_token_ids.append(padded)
# Convert to MLX array with batch dimension
input_ids = mx.array(padded_token_ids)
# Get embeddings for the batch
embeddings = model(input_ids)
# Mean pooling for each sequence in the batch
pooled = embeddings.mean(axis=1) # Shape: (batch_size, hidden_size)
# Convert batch embeddings to numpy
for j in range(len(batch_chunks)):
pooled_list = pooled[j].tolist() # Convert to list
pooled_numpy = np.array(pooled_list, dtype=np.float32)
all_embeddings.append(pooled_numpy)
# Stack numpy arrays
return np.stack(all_embeddings)
def compute_embeddings_ollama(
texts: list[str], model_name: str, is_build: bool = False, host: str = "http://localhost:11434"
) -> np.ndarray:
"""
Compute embeddings using Ollama API with simplified batch processing.
Uses batch size of 32 for MPS/CPU and 128 for CUDA to optimize performance.
Args:
texts: List of texts to compute embeddings for
model_name: Ollama model name (e.g., "nomic-embed-text", "mxbai-embed-large")
is_build: Whether this is a build operation (shows progress bar)
host: Ollama host URL (default: http://localhost:11434)
Returns:
Normalized embeddings array, shape: (len(texts), embedding_dim)
"""
try:
import requests
except ImportError:
raise ImportError(
"The 'requests' library is required for Ollama embeddings. Install with: uv pip install requests"
)
if not texts:
raise ValueError("Cannot compute embeddings for empty text list")
logger.info(
f"Computing embeddings for {len(texts)} texts using Ollama API, model: '{model_name}'"
)
# Check if Ollama is running
try:
response = requests.get(f"{host}/api/version", timeout=5)
response.raise_for_status()
except requests.exceptions.ConnectionError:
error_msg = (
f"❌ Could not connect to Ollama at {host}.\n\n"
"Please ensure Ollama is running:\n"
" • macOS/Linux: ollama serve\n"
" • Windows: Make sure Ollama is running in the system tray\n\n"
"Installation: https://ollama.com/download"
)
raise RuntimeError(error_msg)
except Exception as e:
raise RuntimeError(f"Unexpected error connecting to Ollama: {e}")
# Check if model exists and provide helpful suggestions
try:
response = requests.get(f"{host}/api/tags", timeout=5)
response.raise_for_status()
models = response.json()
model_names = [model["name"] for model in models.get("models", [])]
# Filter for embedding models (models that support embeddings)
embedding_models = []
suggested_embedding_models = [
"nomic-embed-text",
"mxbai-embed-large",
"bge-m3",
"all-minilm",
"snowflake-arctic-embed",
]
for model in model_names:
# Check if it's an embedding model (by name patterns or known models)
base_name = model.split(":")[0]
if any(emb in base_name for emb in ["embed", "bge", "minilm", "e5"]):
embedding_models.append(model)
# Check if model exists (handle versioned names) and resolve to full name
resolved_model_name = None
for name in model_names:
# Exact match
if model_name == name:
resolved_model_name = name
break
# Match without version tag (use the versioned name)
elif model_name == name.split(":")[0]:
resolved_model_name = name
break
if not resolved_model_name:
error_msg = f"❌ Model '{model_name}' not found in local Ollama.\n\n"
# Suggest pulling the model
error_msg += "📦 To install this embedding model:\n"
error_msg += f" ollama pull {model_name}\n\n"
# Show available embedding models
if embedding_models:
error_msg += "✅ Available embedding models:\n"
for model in embedding_models[:5]:
error_msg += f"{model}\n"
if len(embedding_models) > 5:
error_msg += f" ... and {len(embedding_models) - 5} more\n"
else:
error_msg += "💡 Popular embedding models to install:\n"
for model in suggested_embedding_models[:3]:
error_msg += f" • ollama pull {model}\n"
error_msg += "\n📚 Browse more: https://ollama.com/library"
raise ValueError(error_msg)
# Use the resolved model name for all subsequent operations
if resolved_model_name != model_name:
logger.info(f"Resolved model name '{model_name}' to '{resolved_model_name}'")
model_name = resolved_model_name
# Verify the model supports embeddings by testing it
try:
test_response = requests.post(
f"{host}/api/embeddings", json={"model": model_name, "prompt": "test"}, timeout=10
)
if test_response.status_code != 200:
error_msg = (
f"⚠️ Model '{model_name}' exists but may not support embeddings.\n\n"
f"Please use an embedding model like:\n"
)
for model in suggested_embedding_models[:3]:
error_msg += f"{model}\n"
raise ValueError(error_msg)
except requests.exceptions.RequestException:
# If test fails, continue anyway - model might still work
pass
except requests.exceptions.RequestException as e:
logger.warning(f"Could not verify model existence: {e}")
# Determine batch size based on device availability
# Check for CUDA/MPS availability using torch if available
batch_size = 32 # Default for MPS/CPU
try:
import torch
if torch.cuda.is_available():
batch_size = 128 # CUDA gets larger batch size
elif hasattr(torch.backends, "mps") and torch.backends.mps.is_available():
batch_size = 32 # MPS gets smaller batch size
except ImportError:
# If torch is not available, use conservative batch size
batch_size = 32
logger.info(f"Using batch size: {batch_size}")
def get_batch_embeddings(batch_texts):
"""Get embeddings for a batch of texts."""
all_embeddings = []
failed_indices = []
for i, text in enumerate(batch_texts):
max_retries = 3
retry_count = 0
# Truncate very long texts to avoid API issues
truncated_text = text[:8000] if len(text) > 8000 else text
while retry_count < max_retries:
try:
response = requests.post(
f"{host}/api/embeddings",
json={"model": model_name, "prompt": truncated_text},
timeout=30,
)
response.raise_for_status()
result = response.json()
embedding = result.get("embedding")
if embedding is None:
raise ValueError(f"No embedding returned for text {i}")
if not isinstance(embedding, list) or len(embedding) == 0:
raise ValueError(f"Invalid embedding format for text {i}")
all_embeddings.append(embedding)
break
except requests.exceptions.Timeout:
retry_count += 1
if retry_count >= max_retries:
logger.warning(f"Timeout for text {i} after {max_retries} retries")
failed_indices.append(i)
all_embeddings.append(None)
break
except Exception as e:
retry_count += 1
if retry_count >= max_retries:
logger.error(f"Failed to get embedding for text {i}: {e}")
failed_indices.append(i)
all_embeddings.append(None)
break
return all_embeddings, failed_indices
# Process texts in batches
all_embeddings = []
all_failed_indices = []
# Setup progress bar if needed
show_progress = is_build or len(texts) > 10
try:
if show_progress:
from tqdm import tqdm
except ImportError:
show_progress = False
# Process batches
num_batches = (len(texts) + batch_size - 1) // batch_size
if show_progress:
batch_iterator = tqdm(range(num_batches), desc="Computing Ollama embeddings")
else:
batch_iterator = range(num_batches)
for batch_idx in batch_iterator:
start_idx = batch_idx * batch_size
end_idx = min(start_idx + batch_size, len(texts))
batch_texts = texts[start_idx:end_idx]
batch_embeddings, batch_failed = get_batch_embeddings(batch_texts)
# Adjust failed indices to global indices
global_failed = [start_idx + idx for idx in batch_failed]
all_failed_indices.extend(global_failed)
all_embeddings.extend(batch_embeddings)
# Handle failed embeddings
if all_failed_indices:
if len(all_failed_indices) == len(texts):
raise RuntimeError("Failed to compute any embeddings")
logger.warning(
f"Failed to compute embeddings for {len(all_failed_indices)}/{len(texts)} texts"
)
# Use zero embeddings as fallback for failed ones
valid_embedding = next((e for e in all_embeddings if e is not None), None)
if valid_embedding:
embedding_dim = len(valid_embedding)
for i, embedding in enumerate(all_embeddings):
if embedding is None:
all_embeddings[i] = [0.0] * embedding_dim
# Remove None values
all_embeddings = [e for e in all_embeddings if e is not None]
if not all_embeddings:
raise RuntimeError("No valid embeddings were computed")
# Validate embedding dimensions
expected_dim = len(all_embeddings[0])
inconsistent_dims = []
for i, embedding in enumerate(all_embeddings):
if len(embedding) != expected_dim:
inconsistent_dims.append((i, len(embedding)))
if inconsistent_dims:
error_msg = f"Ollama returned inconsistent embedding dimensions. Expected {expected_dim}, but got:\n"
for idx, dim in inconsistent_dims[:10]: # Show first 10 inconsistent ones
error_msg += f" - Text {idx}: {dim} dimensions\n"
if len(inconsistent_dims) > 10:
error_msg += f" ... and {len(inconsistent_dims) - 10} more\n"
error_msg += f"\nThis is likely an Ollama API bug with model '{model_name}'. Please try:\n"
error_msg += "1. Restart Ollama service: 'ollama serve'\n"
error_msg += f"2. Re-pull the model: 'ollama pull {model_name}'\n"
error_msg += (
"3. Use sentence-transformers instead: --embedding-mode sentence-transformers\n"
)
error_msg += "4. Report this issue to Ollama: https://github.com/ollama/ollama/issues"
raise ValueError(error_msg)
# Convert to numpy array and normalize
embeddings = np.array(all_embeddings, dtype=np.float32)
# Normalize embeddings (L2 normalization)
norms = np.linalg.norm(embeddings, axis=1, keepdims=True)
embeddings = embeddings / (norms + 1e-8) # Add small epsilon to avoid division by zero
logger.info(f"Generated {len(embeddings)} embeddings, dimension: {embeddings.shape[1]}")
return embeddings
def compute_embeddings_gemini(
texts: list[str], model_name: str = "text-embedding-004", is_build: bool = False
) -> np.ndarray:
"""
Compute embeddings using Google Gemini API.
Args:
texts: List of texts to compute embeddings for
model_name: Gemini model name (default: "text-embedding-004")
is_build: Whether this is a build operation (shows progress bar)
Returns:
Embeddings array, shape: (len(texts), embedding_dim)
"""
try:
import os
import google.genai as genai
except ImportError as e:
raise ImportError(f"Google GenAI package not installed: {e}")
api_key = os.getenv("GEMINI_API_KEY")
if not api_key:
raise RuntimeError("GEMINI_API_KEY environment variable not set")
# Cache Gemini client
cache_key = "gemini_client"
if cache_key in _model_cache:
client = _model_cache[cache_key]
else:
client = genai.Client(api_key=api_key)
_model_cache[cache_key] = client
logger.info("Gemini client cached")
logger.info(
f"Computing embeddings for {len(texts)} texts using Gemini API, model: '{model_name}'"
)
# Gemini supports batch embedding
max_batch_size = 100 # Conservative batch size for Gemini
all_embeddings = []
try:
from tqdm import tqdm
total_batches = (len(texts) + max_batch_size - 1) // max_batch_size
batch_range = range(0, len(texts), max_batch_size)
batch_iterator = tqdm(
batch_range, desc="Computing embeddings", unit="batch", total=total_batches
)
except ImportError:
# Fallback when tqdm is not available
batch_iterator = range(0, len(texts), max_batch_size)
for i in batch_iterator:
batch_texts = texts[i : i + max_batch_size]
try:
# Use the embed_content method from the new Google GenAI SDK
response = client.models.embed_content(
model=model_name,
contents=batch_texts,
config=genai.types.EmbedContentConfig(
task_type="RETRIEVAL_DOCUMENT" # For document embedding
),
)
# Extract embeddings from response
for embedding_data in response.embeddings:
all_embeddings.append(embedding_data.values)
except Exception as e:
logger.error(f"Batch {i} failed: {e}")
raise
embeddings = np.array(all_embeddings, dtype=np.float32)
logger.info(f"Generated {len(embeddings)} embeddings, dimension: {embeddings.shape[1]}")
return embeddings