Concurrency
Blocking the Tokio Runtime and How to Find the Culprit
One blocking call inside an async task can freeze a worker thread. See how it happens, how to find it and the three fixes: spawn_blocking, a thread, or async APIs.
7 min read
Topic
Performance
Profilers, flamegraphs, benchmarks and caches: find the slow part first, then fix only that.
Generics
Static Versus Dynamic Dispatch in Rust and the Real Cost
Static dispatch resolves the call at compile time and dynamic dispatch looks it up in a vtable at run time. See the layout, the cost and when it matters.
8 min read
Performance
Release Mode Versus Debug Mode in Rust and the Speed Gap
cargo build is slow to run and fast to compile, cargo build --release is the reverse. See what each profile changes, how to measure the gap and how to tune the dev profile.
2 min read
Generics
Generics in Rust and How Monomorphization Makes Them Fast
Generic Rust code is compiled once per concrete type, which is why it is as fast as hand written code and why binaries grow. See what that looks like.
6 min read
Performance
Rust Performance Basics Measure First Then Change One Thing
The handful of habits behind most Rust speed: build in release, avoid needless allocation, use iterators and slices, pick the right collection and measure before tuning.
2 min read
Generics
Box dyn Trait in Rust and When Allocation Is Worth It
Box<dyn Trait> costs one allocation and one indirect call per use. Learn what that costs, when it is worth it and the cheaper alternatives.
8 min read
Rust
Rust Collections Compared Vec HashMap HashSet and BTreeMap
Choose between Vec, VecDeque, HashMap, HashSet, BTreeMap and BTreeSet by the operations you need, with complexity, ordering and memory notes.
8 min read
PerformanceGuide
Profiling Rust Programs From Flamegraph to a Fix Guide
A guide to making Rust programs faster by measuring first: release builds, flamegraphs, allocation counts, benchmarks and the order to look at things.
14 min read
Rust
Integer Overflow in Rust and Why Debug and Release Differ
Integer overflow panics in a debug build and wraps in a release build. See the exact behavior, the checked, wrapping and saturating methods, and the setting that changes it.
6 min read
Get new posts by email
We send one email when a new post is published. No spam.