START {Note Type} {Note Fields} Tags: END START Basic This is a test. Back: Test successful! Tags: Testing <!--ID: 1751507777788--> END # System Design Cheat Sheet **Low Latency Storage**: #flashcard Redis for Low Latency (feed, cache) <!--ID: 1751507777790--> Traffic Surge: #flashcard Message Queue for Traffic management <!--ID: 1751507777793--> Real-Time communication #flashcard Redis PubSub - ALL to ALL server to Redis instances, high scale Consistent hashing #flashcard Add users to specific servers via Zookeeper config <!--ID: 1751507777795--> Optimized Search - large #flashcard ElasticSearch <!--ID: 1751507777797--> Optimized Search - small #flashcard PostGres FTS plugin <!--ID: 1751507777799--> GeoLocation - high traffic writes: #flashcard Redis Geohash <!--ID: 1751507777801--> GeoLocation - Read-heavy and infrequent writes: #flashcard QuadTree/R-Tree via PostGIS or ES <!--ID: 1751507777803--> File Upload #flashcard * Presigned S3 URLS * Client side Chunking <!--ID: 1751507777805--> Video Processing #flashcard Server side chunking for bitrates and smaller sizes <!--ID: 1751507777808--> Write-heavy Database #flashcard Cassandra for Write Heavy <!--ID: 1751507777810--> Standard Database #flashcard PostGres standard <!--ID: 1751507777812--> Aggregation - real-time #flashcard Flink <!--ID: 1751507777814--> Aggregation - batch #flashcard Spark <!--ID: 1751507777816--> Message Queue - high scalability #flashcard Kafka <!--ID: 1751507777818--> Message Queue - Async, retry, visibility timeout #flashcard SQS <!--ID: 1751507777821-->