Beginner

Introduction to DVC

Understand why Git alone is not enough for machine learning projects and how DVC extends Git to handle large data files, models, and ML pipelines.

The Problem

Machine learning projects involve more than just code. They include large datasets (GBs or TBs), trained models, and intermediate outputs. Git was designed for source code — it cannot efficiently handle large binary files.

Without proper versioning, ML teams face common problems:

  • Datasets stored in shared drives with names like data_v3_final_FINAL.csv
  • No way to reproduce an experiment from 3 months ago
  • Model files tracked in Git, bloating the repository
  • No connection between code version, data version, and model version

What is DVC?

DVC (Data Version Control) is an open-source tool that extends Git to handle data, models, and pipelines. It uses Git for metadata and lightweight pointers while storing actual data in remote storage (S3, GCS, Azure Blob, SSH, etc.).

📦

Data Versioning

Track large files and directories with Git-like commands. Switch between data versions using Git branches and tags.

🔧

ML Pipelines

Define multi-stage pipelines in YAML. DVC tracks dependencies and only reruns stages that have changed.

📊

Experiment Tracking

Run experiments with different parameters, compare metrics, and manage results without creating Git branches.

🔒

Reproducibility

Every experiment is fully reproducible: code (Git) + data (DVC) + parameters (params.yaml) = exact replica.

How DVC Works

Architecture — DVC + Git
Your Git Repository:
  ├── src/
  │   ├── train.py          # Code (tracked by Git)
  │   └── preprocess.py
  ├── params.yaml            # Parameters (tracked by Git)
  ├── data/
  │   └── train.csv.dvc      # DVC pointer file (tracked by Git)
  ├── models/
  │   └── model.pkl.dvc      # DVC pointer file (tracked by Git)
  ├── dvc.yaml               # Pipeline definition (tracked by Git)
  ├── dvc.lock               # Pipeline state (tracked by Git)
  └── .dvc/
      └── config             # DVC configuration

Remote Storage (S3, GCS, etc.):
  └── cache/
      ├── ab/cdef1234...     # Actual data file (content-addressed)
      └── 12/3456abcd...     # Actual model file

DVC vs Alternatives

FeatureDVCGit LFSW&B ArtifactsMLflow
LicenseApache 2.0Open sourceSaaSApache 2.0
Data versioningExcellentGoodGoodVia artifacts
ML pipelinesBuilt-inNoNoVia Projects
Storage backendsS3, GCS, Azure, SSH, localGit serverW&B cloudS3, GCS, local
Git integrationNative (extends Git)NativeIndependentIndependent
Experiment trackingBuilt-in (CLI)NoExcellent (UI)Excellent (UI)
When to choose DVC: DVC is ideal when you want to keep data versioning tightly coupled with Git, need reproducible pipelines, and prefer open-source self-hosted solutions. It pairs well with W&B for visualization (DVC for data, W&B for experiment UI).
💡
Prerequisites: Basic familiarity with Git (commit, branch, push, pull). Command-line comfort. Python knowledge is helpful but not required for basic data versioning.