heed VS sled

At Meilisearch we are currently trying to add a better error handling in heed v0.20, our LMDB key-value store wrapper. Unfortunately, when there are a lot of generics it can become harder to play with…

There are issues and pull requests but I advise you to look at the milli folder in the Meilisearch repository, it’s where all the logic is done. We extensively use RoaringBitmaps, heed the LMDB wrapper and grenad when indexing.

I’ll continue to introduce new features and new safety guards until v0.20.0. Can you tell me more about your project? Or is it private?

LMDB support multiple readers and one writer at the same time. It is ensured by the library. Note that LMDB is a key-value store. You can use the heed library which is the most maintained Rust wrapper.

Note that heed is ensuring that you are not trying to use transactions, databases and environments in the right way. I have added much more work in that regard in the important update that I am working on too!

I am currently working on exposing the new LMDB encryption feature from heed the safe LMDB wrapper with the help of the Cryptography community.

Have you considered heed or even sanakirja?

rkv hasn't been updated for a while. I recommend using heed - https://docs.rs/heed

For wrappers around LMBD, I'd recommend RKV or Heed https://github.com/mozilla/rkv https://github.com/Kerollmops/heed

a few times, seems interesting. The author's also built a lot of other cool concurrency primitives for Rust as well.

[0] https://github.com/spacejam/sled

- Dropbox [3] uses a similar approach but they talk about it a bit more abstractly.

Sans-IO is more documented in Python [4], but str0m [5] and quinn-proto [6] are the best examples in Rust I’m aware of. Note that sans-IO is orthogonal to deterministic test frameworks, but it composes well with them.

With the disclaimer that my opinions are mine and mine alone, and don’t reflect the company I work at —— I do work at a rust shop that has utilized these techniques on some projects.

TigerBeetle is an amazing example and I’ve looked at it before! They are really the best example of this approach outside of FoundationDB I think.

[0]: https://risingwave.com/blog/deterministic-simulation-a-new-e...

[1]: https://risingwave.com/blog/applying-deterministic-simulatio...

[2]: https://dropbox.tech/infrastructure/-testing-our-new-sync-en...

[3]: https://github.com/spacejam/sled

[4]: https://fractalideas.com/blog/sans-io-when-rubber-meets-road...

[5]: https://github.com/algesten/str0m

[6]: https://docs.rs/quinn-proto/0.10.6/quinn_proto/struct.Connec...

Sled uses bw-tree actually https://github.com/spacejam/sled/wiki/sled-architectural-outlook

There is a valid argument to be made for threads over async in a large percentage of use cases where async is considered the default. If this is what you are referring to however, I don't think they ever referred to async as completely useless: https://github.com/spacejam/sled/issues/1123.

Have you looked into other pure-Rust databases as well, such as sled or GlueSQL which has an SQL interface on top of sled? I wonder how those would compare to Persy.

I'm not sure what you need. Are these of any use? https://github.com/meilisearch/heed https://github.com/spacejam/sled

There is also Sled but as I understand it that is being reworked to use the author's new DB core Marble

There are some databases like sled/FlashDB designed to be embedded to other applications even bare metal microcontrollers. But I do doubt the potential bussiness value of a pure embedded database.

https://github.com/spacejam/sled

To add transaction support, you probably need a good understanding of how the memtable works in Log Structured Merge trees: