Table of Content
There are multiple integrations with cargo that simplify your life a lot .
flamegraph works in any
platform that has dtrace or perf support.
$ cargo install flamegraph
$ cargo flamegraph -o flame.svg -b rav1e -- ~/sample.y4m -o /dev/null
$ $browser flame.svg
NOTE Make sure the browser lets you use the built-in interactivity in the svg.
cargo-instruments is macOS-only and integrates neatly with the XCode UI.
$ cargo install cargo-instruments
$ cargo instruments --release --open --bin rav1e -- ~/sample.y4m -o /dev/null
Most common linux-specific profiler, to use the callgraphs you need dwarf debug symbols.
$ cargo build --release
$ perf record --call-graph dwarf target/release/rav1e ~/sample.y4m -o /dev/null
$ perf report
uftrace is an ELF-specific tracer.
It leverages the mcount instrumentation.
$ cargo rustc --release --bin rav1e -- -Z instrument-mcount
$ uftrace record --no-libcall -D 5 target/release/rav1e ~/sample.y4m -o /dev/null
$ uftrace report
We use rust_hawktracer to
measure specific codepath timings. Building --features=tracing enables it.
Use the standard hawktrace-convert to produce graphs.
cargo-asm can be used to inspect the assembly generated by the Rust compiler. This can be helpful for micro-optimizations including coercing the compiler to auto-vectorize a function.
Simple setup:
- Install cargo-asm:
cargo install cargo-asm - Generate the list of functions:
cargo asm > fn.list - Search for the function you want to analyze:
grep cdef_dist fn.list- If the function doesn't appear, it may be inlined by the compiler.
You can temporarily add
#[inline(never)]to the function to bypass this issue.
- If the function doesn't appear, it may be inlined by the compiler.
You can temporarily add
- Generate ASM for your function:
cargo asm rav1e::rdo::cdef_dist_wxh --no-color > out.asm