Simon Willison’s Weblog


Monday, 30th October 2017

Scaling the GitLab database. Lots of interesting details on how GitLab have worked to scale their PostgreSQL setup. They’ve avoided sharding so far, instead opting for database pooling with pgbouncer and read-only replicas using hot standbys. I like the way they deal with replica lag—they store the current WAL position in a redis key for the user every time there’s a write, then use pg_last_xlog_replay_location() on the various replicas to check and see if they have caught up next time the user makes a request that needs to read some data. # 8:53 pm

Fun facts about Rust’s growing popularity. TIL Rust is used “on hundreds of millions of desktops via Dropbox”. And Rust developers are called Rustaceans. # 4:45 am