Baidu, China's largest internet services company, has deployed a massive MongoDB cluster to power over 100 of its products and services, including messaging, photo sharing, metadata storage, and more. The cluster, which spans 600 nodes across multiple locations, stores over 200 billion documents with up to 5 replica set members and manages over 1 PB of data. MongoDB's distributed design and native JSON data model have provided the scale required for Baidu's growing user base, while the WiredTiger storage engine has enabled efficient data management. The company's experience with MongoDB has been instrumental in its widespread adoption across the organization, and it continues to be a key component of its scalable database architecture.