[tomnipotent]

> What was the struggle?

Performance is always great until you have to hit disk. Not uncommon to rely on mmap at which point your disk access is sub-optimal vs. a hand-tailored buffer manager with strategies to improve disk reads.

[sschnei8]

This requires the obligatory https://db.cs.cmu.edu/mmap-cidr2022/

[mgaunard]

The linux kernel lets you trigger asynchronous writes of the pages as well as synchronous barriers to ensure they've been written.

You don't need to use direct I/O to have fine control.

[fsckboy]

the purpose of a btree is to optimize when you are hitting the disk, you can't call that the struggle, that's when the btree sings (tho you could consider extensible hashing)