Simon Willison’s Weblog

8 items tagged “benjohnson”


Introducing LiteFS (via) LiteFS is the new SQLite replication solution from Fly, now ready for beta testing. It’s from the same author as Litestream but has a very different architecture; LiteFS works by implementing a custom FUSE filesystem which spies on SQLite transactions being written to the journal file and forwards them on to other nodes in the cluster, providing full read-replication. The signature Litestream feature of streaming a backup to S3 should be coming within the next few months. # 21st September 2022, 6:56 pm

How the SQLite Virtual Machine Works. The latest entry in Ben Johnson’s series about SQLite internals. # 7th September 2022, 8:49 pm

How SQLite Scales Read Concurrency (via) Ben Johnson’s series on SQLite internals continues—this time with a detailed explanation of how the SQLite WAL (Write-Ahead Log) is implemented. # 24th August 2022, 4:16 pm

How SQLite Helps You Do ACID (via) Ben Johnson’s series of posts explaining the internals of SQLite continues with a deep look at how the rollback journal works. I’m learning SO much from this series. # 10th August 2022, 3:39 pm

SQLite Internals: Pages & B-trees (via) Ben Johnson provides a delightfully clear introduction to SQLite internals, describing the binary format used to store rows on disk and how SQLite uses 4KB pages for both row storage and for the b-trees used to look up records. # 27th July 2022, 2:57 pm

SQLite Happy Hour—a Twitter Spaces conversation about three interesting projects building on SQLite

Yesterday I hosted SQLite Happy Hour. my first conversation using Twitter Spaces. The idea was to dig into three different projects that were doing interesting things on top of SQLite. I think it worked pretty well, and I’m curious to explore this format more in the future.

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Litestream runs continuously on a test server with generated load and streams backups to S3. It uses physical replication so it’ll actually restore the data from S3 periodically and compare the checksum byte-for-byte with the current database.

Ben Johnson # 11th February 2021, 8:50 pm

Why I Built Litestream. Litestream is a really exciting new piece of technology by Ben Johnson, who previously built BoltDB, the key-value store written in Go that is used by etcd. It adds replication to SQLite by running a process that converts the SQLite WAL log into a stream that can be saved to another folder or pushed to S3. The S3 option is particularly exciting—Ben estimates that keeping a full point-in-time recovery log of a high write SQLite database should cost in the order of a few dollars a month. I think this could greatly expand the set of use-cases for which SQLite is sensible choice. # 11th February 2021, 7:25 pm