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Weights And Biases

通过自动日志记录跟踪机器学习实验,实时可视化训练过程,使用扫描(sweeps)优化超参数,并利用 W&B(协作式 MLOps 平台)管理模型注册表

技能元数据

来源捆绑(默认安装)
路径skills/mlops/evaluation/weights-and-biases
版本1.0.0
作者Orchestra Research
许可证MIT
依赖项wandb
标签MLOps, Weights And Biases, WandB, Experiment Tracking, Hyperparameter Tuning, Model Registry, Collaboration, Real-Time Visualization, PyTorch, TensorFlow, HuggingFace

参考:完整 SKILL.md

信息

以下是 Hermes 在触发此技能时加载的完整技能定义。这是技能激活时代理看到的指令。

Weights & Biases:ML 实验跟踪与 MLOps

何时使用此技能

当您需要执行以下操作时,请使用 Weights & Biases (W&B):

  • 跟踪 ML 实验,自动记录指标
  • 实时可视化训练仪表板
  • 比较运行,跨超参数和配置进行对比
  • 优化超参数,通过自动化扫描
  • 管理模型注册表,包含版本控制和血缘关系
  • 协作开展 ML 项目,使用团队工作区
  • 跟踪工件(数据集、模型、代码)及其血缘关系

用户:200,000+ ML 从业者 | GitHub Stars:10.5k+ | 集成:100+

安装

# Install W&B
pip install wandb

# Login (creates API key)
wandb login

# Or set API key programmatically
export WANDB_API_KEY=your_api_key_here

快速入门

基本实验跟踪

import wandb

# Initialize a run
run = wandb.init(
project="my-project",
config={
"learning_rate": 0.001,
"epochs": 10,
"batch_size": 32,
"architecture": "ResNet50"
}
)

# Training loop
for epoch in range(run.config.epochs):
# Your training code
train_loss = train_epoch()
val_loss = validate()

# Log metrics
wandb.log({
"epoch": epoch,
"train/loss": train_loss,
"val/loss": val_loss,
"train/accuracy": train_acc,
"val/accuracy": val_acc
})

# Finish the run
wandb.finish()

结合 PyTorch 使用

import torch
import wandb

# Initialize
wandb.init(project="pytorch-demo", config={
"lr": 0.001,
"epochs": 10
})

# Access config
config = wandb.config

# Training loop
for epoch in range(config.epochs):
for batch_idx, (data, target) in enumerate(train_loader):
# Forward pass
output = model(data)
loss = criterion(output, target)

# Backward pass
optimizer.zero_grad()
loss.backward()
optimizer.step()

# Log every 100 batches
if batch_idx % 100 == 0:
wandb.log({
"loss": loss.item(),
"epoch": epoch,
"batch": batch_idx
})

# Save model
torch.save(model.state_dict(), "model.pth")
wandb.save("model.pth") # Upload to W&B

wandb.finish()

核心概念

1. 项目(Projects)和运行(Runs)

项目:相关实验的集合 运行:训练脚本的单次执行

# Create/use project
run = wandb.init(
project="image-classification",
name="resnet50-experiment-1", # Optional run name
tags=["baseline", "resnet"], # Organize with tags
notes="First baseline run" # Add notes
)

# Each run has unique ID
print(f"Run ID: {run.id}")
print(f"Run URL: {run.url}")

2. 配置跟踪

自动跟踪超参数:

config = {
# Model architecture
"model": "ResNet50",
"pretrained": True,

# Training params
"learning_rate": 0.001,
"batch_size": 32,
"epochs": 50,
"optimizer": "Adam",

# Data params
"dataset": "ImageNet",
"augmentation": "standard"
}

wandb.init(project="my-project", config=config)

# Access config during training
lr = wandb.config.learning_rate
batch_size = wandb.config.batch_size

3. 指标日志记录

# Log scalars
wandb.log({"loss": 0.5, "accuracy": 0.92})

# Log multiple metrics
wandb.log({
"train/loss": train_loss,
"train/accuracy": train_acc,
"val/loss": val_loss,
"val/accuracy": val_acc,
"learning_rate": current_lr,
"epoch": epoch
})

# Log with custom x-axis
wandb.log({"loss": loss}, step=global_step)

# Log media (images, audio, video)
wandb.log({"examples": [wandb.Image(img) for img in images]})

# Log histograms
wandb.log({"gradients": wandb.Histogram(gradients)})

# Log tables
table = wandb.Table(columns=["id", "prediction", "ground_truth"])
wandb.log({"predictions": table})

4. 模型检查点保存

import torch
import wandb

# Save model checkpoint
checkpoint = {
'epoch': epoch,
'model_state_dict': model.state_dict(),
'optimizer_state_dict': optimizer.state_dict(),
'loss': loss,
}

torch.save(checkpoint, 'checkpoint.pth')

# Upload to W&B
wandb.save('checkpoint.pth')

# Or use Artifacts (recommended)
artifact = wandb.Artifact('model', type='model')
artifact.add_file('checkpoint.pth')
wandb.log_artifact(artifact)

超参数扫描

自动搜索最佳超参数。

定义扫描配置

sweep_config = {
'method': 'bayes', # or 'grid', 'random'
'metric': {
'name': 'val/accuracy',
'goal': 'maximize'
},
'parameters': {
'learning_rate': {
'distribution': 'log_uniform',
'min': 1e-5,
'max': 1e-1
},
'batch_size': {
'values': [16, 32, 64, 128]
},
'optimizer': {
'values': ['adam', 'sgd', 'rmsprop']
},
'dropout': {
'distribution': 'uniform',
'min': 0.1,
'max': 0.5
}
}
}

# Initialize sweep
sweep_id = wandb.sweep(sweep_config, project="my-project")

定义训练函数

def train():
# Initialize run
run = wandb.init()

# Access sweep parameters
lr = wandb.config.learning_rate
batch_size = wandb.config.batch_size
optimizer_name = wandb.config.optimizer

# Build model with sweep config
model = build_model(wandb.config)
optimizer = get_optimizer(optimizer_name, lr)

# Training loop
for epoch in range(NUM_EPOCHS):
train_loss = train_epoch(model, optimizer, batch_size)
val_acc = validate(model)

# Log metrics
wandb.log({
"train/loss": train_loss,
"val/accuracy": val_acc
})

# Run sweep
wandb.agent(sweep_id, function=train, count=50) # Run 50 trials

扫描策略

# Grid search - exhaustive
sweep_config = {
'method': 'grid',
'parameters': {
'lr': {'values': [0.001, 0.01, 0.1]},
'batch_size': {'values': [16, 32, 64]}
}
}

# Random search
sweep_config = {
'method': 'random',
'parameters': {
'lr': {'distribution': 'uniform', 'min': 0.0001, 'max': 0.1},
'dropout': {'distribution': 'uniform', 'min': 0.1, 'max': 0.5}
}
}

# Bayesian optimization (recommended)
sweep_config = {
'method': 'bayes',
'metric': {'name': 'val/loss', 'goal': 'minimize'},
'parameters': {
'lr': {'distribution': 'log_uniform', 'min': 1e-5, 'max': 1e-1}
}
}

工件(Artifacts)

跟踪数据集、模型和其他文件及其血缘关系。

记录工件

# Create artifact
artifact = wandb.Artifact(
name='training-dataset',
type='dataset',
description='ImageNet training split',
metadata={'size': '1.2M images', 'split': 'train'}
)

# Add files
artifact.add_file('data/train.csv')
artifact.add_dir('data/images/')

# Log artifact
wandb.log_artifact(artifact)

使用工件

# Download and use artifact
run = wandb.init(project="my-project")

# Download artifact
artifact = run.use_artifact('training-dataset:latest')
artifact_dir = artifact.download()

# Use the data
data = load_data(f"{artifact_dir}/train.csv")

模型注册表

# Log model as artifact
model_artifact = wandb.Artifact(
name='resnet50-model',
type='model',
metadata={'architecture': 'ResNet50', 'accuracy': 0.95}
)

model_artifact.add_file('model.pth')
wandb.log_artifact(model_artifact, aliases=['best', 'production'])

# Link to model registry
run.link_artifact(model_artifact, 'model-registry/production-models')

集成示例

HuggingFace Transformers

from transformers import Trainer, TrainingArguments
import wandb

# Initialize W&B
wandb.init(project="hf-transformers")

# Training arguments with W&B
training_args = TrainingArguments(
output_dir="./results",
report_to="wandb", # Enable W&B logging
run_name="bert-finetuning",
logging_steps=100,
save_steps=500
)

# Trainer automatically logs to W&B
trainer = Trainer(
model=model,
args=training_args,
train_dataset=train_dataset,
eval_dataset=eval_dataset
)

trainer.train()

PyTorch Lightning

from pytorch_lightning import Trainer
from pytorch_lightning.loggers import WandbLogger
import wandb

# Create W&B logger
wandb_logger = WandbLogger(
project="lightning-demo",
log_model=True # Log model checkpoints
)

# Use with Trainer
trainer = Trainer(
logger=wandb_logger,
max_epochs=10
)

trainer.fit(model, datamodule=dm)

Keras/TensorFlow

import wandb
from wandb.keras import WandbCallback

# Initialize
wandb.init(project="keras-demo")

# Add callback
model.fit(
x_train, y_train,
validation_data=(x_val, y_val),
epochs=10,
callbacks=[WandbCallback()] # Auto-logs metrics
)

可视化与分析

自定义图表

# Log custom visualizations
import matplotlib.pyplot as plt

fig, ax = plt.subplots()
ax.plot(x, y)
wandb.log({"custom_plot": wandb.Image(fig)})

# Log confusion matrix
wandb.log({"conf_mat": wandb.plot.confusion_matrix(
probs=None,
y_true=ground_truth,
preds=predictions,
class_names=class_names
)})

报告

在 W&B UI 中创建可共享的报告:

  • 组合运行、图表和文本
  • 支持 Markdown
  • 可嵌入的可视化效果
  • 团队协作

最佳实践

1. 使用标签和组进行组织

wandb.init(
project="my-project",
tags=["baseline", "resnet50", "imagenet"],
group="resnet-experiments", # Group related runs
job_type="train" # Type of job
)

2. 记录所有相关信息

# Log system metrics
wandb.log({
"gpu/util": gpu_utilization,
"gpu/memory": gpu_memory_used,
"cpu/util": cpu_utilization
})

# Log code version
wandb.log({"git_commit": git_commit_hash})

# Log data splits
wandb.log({
"data/train_size": len(train_dataset),
"data/val_size": len(val_dataset)
})

3. 使用描述性名称

# ✅ Good: Descriptive run names
wandb.init(
project="nlp-classification",
name="bert-base-lr0.001-bs32-epoch10"
)

# ❌ Bad: Generic names
wandb.init(project="nlp", name="run1")

4. 保存重要工件

# Save final model
artifact = wandb.Artifact('final-model', type='model')
artifact.add_file('model.pth')
wandb.log_artifact(artifact)

# Save predictions for analysis
predictions_table = wandb.Table(
columns=["id", "input", "prediction", "ground_truth"],
data=predictions_data
)
wandb.log({"predictions": predictions_table})

5. 在不稳定连接时使用离线模式

import os

# Enable offline mode
os.environ["WANDB_MODE"] = "offline"

wandb.init(project="my-project")
# ... your code ...

# Sync later
# wandb sync <run_directory>

团队协作

共享运行

# Runs are automatically shareable via URL
run = wandb.init(project="team-project")
print(f"Share this URL: {run.url}")

团队项目

  • 在 wandb.ai 创建团队账户
  • 添加团队成员
  • 设置项目可见性(私有/公开)
  • 使用团队级工件和模型注册表

定价

  • 免费:无限公共项目,100GB 存储
  • 学术版:学生/研究人员免费
  • 团队版:$50/席位/月,私有项目,无限存储
  • 企业版:定制定价,支持本地部署选项

资源

另见

  • references/sweeps.md - 全面的超参数优化指南
  • references/artifacts.md - 数据和模型版本控制模式
  • references/integrations.md - 特定框架的示例