Hacker News: MrCroxx

Do We Still Need Tech Blogs in the Era of GenAI?

MrCroxx — Fri, 23 Jan 2026 10:40:24 +0000

Article URL: https://blog.mrcroxx.com/posts/do-we-still-need-tech-blogs-in-the-era-of-gen-ai/

Comments URL: https://news.ycombinator.com/item?id=46730893

Points: 2

# Comments: 0

New comment by MrCroxx in "Foyer: A Hybrid Cache in Rust – Past, Present, and Future"

MrCroxx — Mon, 20 Oct 2025 06:23:55 +0000

For those who may not know, over the past few months, I've been continuously developing and maintaining a hybrid cache library in Rust, Foyer[0].

However, from the very beginning until now, I haven’t had the chance to properly introduce this project through an article. On one hand, I’m not very skilled at writing in English, so I kept procrastinating. (Thanks to ChatGPT, I can focus more on the content rather than worrying about my limited English writing skill.) On the other hand, Foyer was evolving rapidly in its early stages, undergoing major refactoring almost every few months. As a result, it felt premature to formally introduce the project.

But now, Foyer has already gained more stars on Github than than the project it was originally inspired by — Facebook’s CacheLib[1]. This excites me and makes me worry even more about the future of Foyer. So, I think it's time to write a proper blog to introduce it.

[0]: https://github.com/foyer-rs/foyer

[1]: https://github.com/facebook/cachelib

Foyer: A Hybrid Cache in Rust – Past, Present, and Future

MrCroxx — Mon, 20 Oct 2025 06:23:55 +0000

Article URL: https://blog.mrcroxx.com/posts/foyer-a-hybrid-cache-in-rust-past-present-and-future/

Comments URL: https://news.ycombinator.com/item?id=45640577

Points: 3

# Comments: 1

New comment by MrCroxx in "I built Foyer: a Rust hybrid cache that slashes S3 latency"

MrCroxx — Sun, 28 Sep 2025 05:47:50 +0000

Hi, foyer's author here. The "zero-copy in-memory abstraction" is compared to Facebook's CacheLib.

CacheLib requires entries to be copied to the CacheLib managed memory when it's inserted. It simplified some design trade-offs, but may affect the overall throughput when in-memory cache is involved more than nvm cache. FYI: https://cachelib.org/docs/Cache_Library_User_Guides/Write_da...

Foyer only requries entries to be serialized/deserialized when writing/reading from disk. The in-memory cache doesn't force a deep memory copy.

New comment by MrCroxx in "I built Foyer: a Rust hybrid cache that slashes S3 latency"

MrCroxx — Sun, 28 Sep 2025 05:37:24 +0000

Hi, foyer's author here. Page cache and swap are indeed good general proposed strategies and continuously evoluting. There are several reasons why foyer manages memory and disk control by itself rather than directly utilizing these mechanisms:

1. Leverage asynchronous capabilities: Foyer exposes async interfaces so that while waiting for IO and other operations, the worker can still perform other tasks, thereby increasing overall throughput. If swap is used, a page fault will cause synchronous waiting, blocking the worker thread and resulting in performance degradation.

2. Fine-grained control: As a dedicated cache system, foyer has a better understanding than a general proposed system like the operating system's page cache of which data should be cached and which should not. This is also why foyer has supported direct I/O to avoid duplication of abilities with the page cache since day one. Foyer can use its own strategies to know earlier when data should be cached or evicted.

New comment by MrCroxx in "Zig's new LinkedList API (it's time to learn fieldParentPtr)"

MrCroxx — Mon, 14 Apr 2025 14:34:13 +0000

Agreed. Intrusive data structures are good for implementing multi-container data structures with lower allocation overhead. And they are widely used than expected. E.g. LRU is a classic multi-container problem.

New comment by MrCroxx in "A lightweight unified metrics library in Rust for various metrics system"

MrCroxx — Sat, 12 Apr 2025 08:13:58 +0000

While I was developing [foyer](https://github.com/foyer-rs/foyer), which is a hybrid in-memory and disk cache project in Rust. Some users asked for metrics system support for both the Prometheus ecosystem and OpenTelemetry ecosystem. After investigating and trying out some libs, I decided to develop a new lib that is lightweight, support both Prometheus and OpenTelemety, and even different version of `prometheus`, `prometheus-client` and `opentelemetry` crates for various users.

Show HN: Mixtrics - A lightweight metrics lib in Rust for various metrics system

MrCroxx — Sat, 12 Apr 2025 08:13:58 +0000

Article URL: https://github.com/foyer-rs/mixtrics

Comments URL: https://news.ycombinator.com/item?id=43662422

Points: 4

# Comments: 1

New comment by MrCroxx in "Apple pulls data protection tool after UK government security row"

MrCroxx — Sat, 22 Feb 2025 14:42:12 +0000

I'm drunk. No offense. Why our world ends up like this.