It’s hard to overstate the reputation of the author of this post. Everything good about GitHub’s internal systems seemed to have his name all over it (I realize that today this statement hits different than a few years ago). Our times at GH didn’t overlap much but hearing the fact that he’s working at cursor increases my estimation of their engineering org by leaps and bounds.
> The "fan-out" is synchronized with a classic consensus algorithm called 3PC (three-phase commit) so that a push is only accepted if a majority of the nodes acknowledge it.
Doesn't 3PC require all nodes to agree, not just a majority?
> What about consensus? Elections? Which server is the primary for a given repository? It also doesn't matter! There's no state and no consensus here. Any server can be the primary. All updates to the write-ahead log are synchronized with an atomic compare-and-swap (CAS) operation on S3, so it's always safe for any instance of a repository to receive a push.
Again reminded of what an amaizing piece of engineering S3 is (99.999999999% - 11 nines of durability) [1]
Doesn't 3PC require all nodes to agree, not just a majority?
Again reminded of what an amaizing piece of engineering S3 is (99.999999999% - 11 nines of durability) [1]
1: https://docs.aws.amazon.com/AmazonS3/latest/userguide/DataDu...
How many startups and corporations built on top of S3 semantics?
Snowflake and the big lakehouses are one of them. They use S3 as giant disk in the sky.
Cursor Origin Code Hosting
https://news.ycombinator.com/item?id=49334209