System Design Codex's resource offers insights, tutorials, and resources for software architects and system designers. Readers can learn about system architecture patterns, scalability principles, and distributed computing concepts. With articles, case studies, and design principles, System Design Codex provides  guidance and expertise for designing robust and scalable software systems.

System Design Codex

Reddit built a unified media metadata store to consolidate scattered metadata from multiple systems into a single AWS Aurora Postgres database. The system handles 100K+ read requests per second with p50 latency of 2.6ms and p99 of 17ms. The migration used dual writes, backfill, and a Kafka-based Change Data Capture pipeline to detect and fix inconsistencies. For future scalability toward an estimated 50TB by 2030, Reddit implemented range-based partitioning using pg_partman and pg_cron, leveraging monotonically increasing post_id values to keep recent partition indexes cached in the buffer pool.

Inside Look at Reddit's Metadata Store