#prog #rust #article

How we saved 100 terabytes of memory by optimizing 1.1.1.1’s DNS cache

Big Pineapple, the platform behind 1.1.1.1, Gateway DNS, DNS Firewall, AS112, and several other Cloudflare DNS services, stores over 250 billion DNS cache entries at any given time. At that scale, wasting a single byte per entry costs more than 250 gigabytes of memory across our fleet.

Five successive changes to how cache entries are stored in memory cut the per-entry footprint by over 50%. Across our fleet, these changes freed up roughly 100 terabytes of memory, equivalent to the amount of RAM in 130 of our Gen 13 servers. The cache also got faster. Insert throughput rose 43% and lookup latency dropped 19%, as fewer allocations and better memory locality meant we did not trade speed for space.

Большая часть изменений довольно простая.

#prog #rust #article

How I made Rustdoc 33% faster in one week

More than any technical detail, the learnings I most want you to take away are to trust your instincts and to question assumptions. Just because a piece of code (or anything, not just code!) has been a certain way for a long time doesn’t mean that it’s optimal or even correct.

#prog #js #abnormalprogramming #article

The Depths of JavaScript: Minesweeper in 247 Bytes

b=e=>document.body.innerHTML=m(73,e||[~9,..."1172711",~9].map(j=>m[i-=j]?++e:i).map(j=>b(b[i=j]^1|e),b[i]=!m[O--,i]*~e));b(m=t=>t--?`<a onmouseup=b(b[i=${t}]^=event.which)>${t%9?"*#F"[x=b[t]??=(O-=m[t]=Math.random()<.1,1)]??~x:"<p>"}`+m(t):O,O=64)

#prog #rust #article

iddqd, or the hardest kind of unsafe Rust

I’m the main author of iddqd, a Rust library for maps (named after the Doom cheat code) where keys are borrowed from values. <...>

iddqd consists of a fair amount of unsafe code underneath. There’s been some recent concern over the amount of unsafe code in Rust rewrites, so I thought I’d write about some of the unsafe code in iddqd and how we try to tame it.

#prog #article

Implementing FMA and finding bugs in C and Rust standard libraries

This is a story of how I tried to compute a * b + c, and found that Rust and musl libc get it subtly wrong.

#prog #rust #article

Plush's New Register-Based Interpreter Is Insanely Fast

I'll go into some detail on how the interpreter was rewritten to switch from a stack-based design like CPython, to a register-based design like Lua, and optimized to deliver some surprising, and I think pretty impressive results. One thing I'll say right away is that if you care about interpreter performance, you probably should not be writing stack-based bytecode interpreters in 2026.

#prog #rust #article

Could Cargo's scheduler be better?

Автор поста собрала записи того, сколько времени уходит на компиляцию каждого крейта во время сборки разных проектов, и решила проверить, можно ли было ускорить сборку за счёт использования порядка сборки, отличного от того, что используется в cargo. В качестве приоритета она использовала т. н. b-level — фактически критический путь в графе зависимостей в терминах длительности компиляции.

TL;DR: этот гипотетический вариант эффективнее cargo и переживает добавление нормально распределённого шума (с разбросом ±60%) и схлопывание информации о длительности до одного бита (долго/недолго).

#prog #rust #rustlib #article

The Design Behind wincode, a Faster Rust Serializer

wincode is a fast, bincode-wire-compatible serializer and deserializer for Rust, built by Anza originally for the Agave validator. It is not a fork of bincode. It is a new implementation with its own traits and derive macros that produces the same bytes as bincode's default configuration

TL;DR: запись в предоставленный MaybeUninit буфер, батчинг валидаций для последовательностей "простых" значений, специализация по типам, использующая сгенерированную derive-макросами метаинформацию (facet на минималках)

#prog #rust #article

Proving my Rust NVR doesn't leak memory (it did)

К сожалению, описанные методы диагностирования специфичны для MacOS

#prog #article

Bespoke: A Programming Language for People Who Say Please

I therefore propose Bespoke, a statically typed and uncompromisingly civilised programming language for developers who believe that machine execution should never come at the expense of good manners. Informally it is known as The Queen’s Code: Victoria’s, naturally; the etiquette committee has yet to approve the twentieth century. Source files use the .charming extension, and the compiler reserves the right to be disappointed in you.

#prog #cpp #quotes

#prog #rust #article

Rust: When Empty Isn't Bottom

Или почему ! в Rust не является bottom типом. TL;DR: в Rust нет отношения подтипизации для типов, не включающих лайфтаймы.

#prog #java #article

JVM Anatomy Quark #23: Compressed References

Спека Java ничего не говорит о том, как представляются ссылки. Как следствие, реализации могут использовать представление ссылок, которые меньше указателя на машине. Статья описывает эти трюки.

Несколько неожиданное следствие: эти трюки работают только на достаточно маленьких кучах, поэтому выделение JVM большего количества памяти может привести к тому, что куча выйдет за этот предел, ссылки перестанут использовать компактное представление и потребление памяти многократно вырастет.

#prog #ml #rust #abnormalprogramming

slopc

A proc macro that uses an hallucination machine to write your function bodies at compile time. Throw a signature, slap #[slop] on it, and pray. If it doesn't compile, it feeds the errors back and retries until it does (or gives up).

(thanks @saddevdiary)

#prog #haskell #article

Type-level programming is still programming

TL;DR: вычисление типов, в отличие от вычисления термов, не является ленивым, и изменения в логике вычисления типов, не меняющее поведение, могут поменять асимптотику времени компиляции с экспоненциальной на линейную.

#prog #rust

Версия binder на Rust вошла в состав ядра в версии 6.18, а в патче, который должен попасть в ядро версии 7.4, старую версию, на C, полностью удалили.

#prog #rust #article

Why building a Rust LSP is hard

This will be a (hopefully coherent) story about how Rust LSPs work, from the perspective of both rust-analyzer and Rust Glancer: how things that seem easy turn out to be hard, things that seem hard turn out to be even harder, and things I didn't expect to exist at all somehow do.

LSP is more of a guess game, where at each step all you are presented with is the potentially incorrect state, and your goal is to guess what would make sense for the user.

#prog #article

Everyone Says Assembly Is Untyped—Everyone Is Wrong

TL;DR: I believe Odin’s inline assembly is currently the best out of any language.

The most important aspects are of this article listed below. I am not aware of any other assembly (GCC/Clang/Rust/Go…) that would combine all of these aspects:

* Inline assembly is organized into asm “templates”, similar to and callable as procedures.
* asm templates integrate with rest of the code, through bindings specifying clobbers, pinned, tied, and scratch registers.
* Assembly syntax is unified across ISAs and consistent with Odin syntax.
* Assembly is fully type checked, just like rest of Odin code.
* Understanding that assembly is actually typed.
* Real semantic diagnostics via core:rexcode encoding tables.
* It was built in ~7 days.



Ну #prog... Кусочек, это и статьёй-то не назвать, скорее, #tips

Printing Lists

To print a comma-separated list, a concise idiom is to optionally print the comma first, before the element:

for (items, 0..) |item, item_index| {
    if (item_index > 0) std.debug.print(", ");
    std.debug.print("{}", .{item});
}

#prog #article

Steering Zig Fmt

TL;DR (но вообще заметка маленькая): zig fmt не имеет the каноничного форматирования для кода, а опирается на указания в виде уже частично отформатированного кода и распространяет его на соседние семантически связанные строки.