[gdwatson]

I will confess to skimming by the end. But I don’t think they explained how they solved the cache issue except to say they rewrote the software in Rust, which is pretty vague.

Was all the code they rewrote originally in Lua? So was it just a matter of moving from a dynamic language with pointer-heavy data structures to a static language with value types and more control over memory layout? Or was there something else going on?

[zozbot234]

The gains in lower memory footprint and lower demands on memory bandwidth from rewriting stuff to Rust are very real, and they're going to matter a lot with DRAM prices being up 5x or more. It doesn't surprise me at all that they would be getting these results.

[gdwatson]

I guess I am a sucker for stories about redesigning data structures, and I'd have liked more detail on that front. Also, they talked about Rust's greater memory safety; it would have been nice to know whether there were specific language features that played into the cache difference or whether it just made the authors comfortable using a systems language in this application and that made the difference.

[jshier]

They posted about the Rust rewrite last year. https://blog.cloudflare.com/20-percent-internet-upgrade/