How Reddit built r/Place

Each year for April Fools’, rather than a prank, we like to create a project that explores the way that humans interact at large scales. This year we came up with Place, a collaborative canvas on which a single user could only place a single tile every five minutes. This limitation de-emphasized the importance of […]

Storing hundreds of millions of simple key-value pairs in Redis

At Instagram, they’re using Redis (comparable to Memcached, but with more options) to map photoIds to userIds. After tweaking their setup — by using Redis hashes (dictionaries that are can be encoded in memory very efficiently) — in Redis, they’ve brought memory usage down from 70MB to 16MB to store 1,000,000 records. While prototyping this […]