Bbtree: Fastest Ordered Map (bbtree.xiangpeng.systems)

105 pointsby aoli-al14 hours ago10 comments

hugmynutus 6 hours ago

[flagged]

xiangpeng 6 hours ago

Hi author here, first of all, thank you for taking time to read the AI slop, you probably already spend more time than I do on this repo, appreciated!

The inline key: yes, it applies to all kinds of integers and strings, and it exposes InlineKey traits that allow you to implement your own inline prefix.

The checklist items: I forget to cross them and they are all implemented, although I think the checklist item has nothing to do with bbtree. but this is definitely a flaw.

hugmynutus 5 hours ago

writing a macro to implement most common integers would've been a time saving.

I also appreciate your paper/work on bf-tree, I started a hobbyist filesystem based on it.

jared_hulbert 11 hours ago

Very nice work. I'm working on stuff... adjacent to this I guess. I've been harping on the ideas that we have to be much more willing to reach for intrinsics, be laser focused on the cache lines, treat DRAM more like an async block device, but I can't believe I haven't thought to show the impact of coherence traffic! When I get some time I might try to apply some of my tricks to bbtree. DM me. I'd love to be able to reach out when I do.

https://news.ycombinator.com/item?id=50218616

geraneum 7 hours ago

> Production-ready by formal verification, model checking, deterministic simulation, fuzzing, and lots of testing.

What does model checking mean here?

aw1621107 6 hours ago

My guess is https://en.wikipedia.org/wiki/Model_checking . C Bounded Model Checker [0] is a relatively well-known instance in the niche.

[0]: https://www.cprover.org/cbmc/

rurban 4 hours ago

No, he used verus, a rust tool. And shuffle and ffs. See his docs

tyilo 8 hours ago

> No human can write better code than LLMs.

Bold claim...

0c3ca83 8 hours ago

Especially since it's trivially proved wrong by inspecting the code. It's invariably awful.

This is only a statement that could be written by someone that doesn't read the code.

ashkankiani 7 hours ago

I had a feeling when I read the title and then started reading the post, "this person must be young, probably a student." I think it's ironic that they're using such unscientific terminology like "fastest" given their background https://xiangpeng.systems/. So clearly, it's in the interest of marketing. Maybe some kind of job advertising/resume thing.

I can almost guarantee that someone has built a custom btree for their specific domain which is faster than this; and that they probably have some or all of the techniques used in this library that are the main contributors to performance, as well. Prefetching is probably the main one they'll claim, and I know personally of some proprietary implementations which have it.

I would like to see some more humility, but I suppose that when you've already resigned your own potential to being below an LLM, then what's the point.

It's not possible or useful for them to grow anymore. Some new frontier model next week will outdo whatever ephemerally useful project this person writes, right? That's the logic?