Struct Profiler 

pub struct Profiler { /* private fields */ }

The Profiler struct is used to trace events.

The events will be stored on disk, if the profiler instance is dropped.

Implementations

impl Profiler

pub fn from_path(path: impl Into<PathBuf>) -> Result<Self, Box<dyn Error>>

Creates a new Profiler with the given path.

The profiling results will be stored at <path>.events, <path>.strings, etc.

Errors

The method will fail if the path does not exist or some other error occurrs while initializing the profiler.

pub fn from_name(name: impl AsRef<str>) -> Result<Self, Box<dyn Error>>

Creates a new Profiler from a given application name.

The profiling results will be stored at ./trace/<name>-<pid>.events, etc.

Errors

The method will fail if the path does not exist or some other error occurrs while initializing the profiler.

Examples found in repository

examples/simple.rs (line 10)

fn main() {
    let profiler = Profiler::from_name("parser").expect("failed to create profiler");
    profiler.enable();

    let result = parse_expression(&profiler, "1234");
    match result {
        Ok(expr) => println!("got expr: {:?}", expr),
        Err(msg) => eprintln!("failed to parse expr: {}", msg),
    }
}

pub fn enable(&self)

Enables the Profiler.

A Profiler, that is created via from_path or from_name, is disabled by default so you have to enable it first using this method.

Examples found in repository

examples/simple.rs (line 11)

fn main() {
    let profiler = Profiler::from_name("parser").expect("failed to create profiler");
    profiler.enable();

    let result = parse_expression(&profiler, "1234");
    match result {
        Ok(expr) => println!("got expr: {:?}", expr),
        Err(msg) => eprintln!("failed to parse expr: {}", msg),
    }
}

pub fn disable(&self)

Disables the Profiler.

This method will make the profiler stop recording any new events but will still write all stored results to disk if dropped.

pub fn trace(&self, category: &str, label: &str) -> Guard<'_>

Starts profiling an event with the given category and label.

Examples found in repository

examples/simple.rs (line 22)

fn parse_expression(profiler: &Profiler, input: &str) -> Result<Expr, &'static str> {
    // We will trace the `parse_expression` function using this.
    let _p = profiler.trace("parsing", "expression");

    input
        .parse::<i64>()
        .map(|num| Expr::Number(num))
        .or_else(|_| {
            if input.chars().all(char::is_alphabetic) {
                Ok(Expr::Identifier(input.to_string()))
            } else {
                Err("invalid identifier")
            }
        })
        .map_err(|_| "invalid expression")
}