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## Binggan
![binggan logo](https://raw.githubusercontent.com/PSeitz/binggan/main/logo_s.png)

Binggan (餅乾, bǐng gān, means cookie in Chinese) is a benchmarking library for Rust.
It is designed to be simple to use and to provide a good overview of the performance of your code and its memory consumption.

### Features

* 📊 Peak Memory Usage
* 💎 Stack Offset Randomization
* 🔌 Plugin System
* 💖 Perf Integration (Linux)
* 🔄 Delta Comparison
* ⚡ Fast Execution
* 🔀 Interleaving Test Runs (More accurate results)
* 🏷️ Named Runs, Groups and Benchmarks
* 🧙 No Macros, No Magic (Just a regular API)
* 🦀 Runs on Stable Rust
* 📈 Custom Reporter
* 🧩 Report Output of Benchmarks
* 🎨 NOW with colored output!

### Example

```rust
use binggan::{black_box, plugins::*, InputGroup, PeakMemAlloc, INSTRUMENTED_SYSTEM};

#[global_allocator]
pub static GLOBAL: &PeakMemAlloc<std::alloc::System> = &INSTRUMENTED_SYSTEM;


fn test_vec(data: &Vec<usize>) {
    // ...
}
fn test_hashmap(data: &Vec<usize>) {
    // ...
}

fn bench_group(mut runner: InputGroup<Vec<usize>>) {
    runner
        // Trashes the CPU cache between runs
        .add_plugin(CacheTrasher::default())
        // Set the peak mem allocator. This will enable peak memory reporting.
        .add_plugin(PeakAllocPlugin::new(GLOBAL))
        // Enables the perf integration. Only on Linux, noop on other OS.
        .add_plugin(PerfCounterPlugin::default());
    // Enables throughput reporting
    runner.throughput(|input| input.len() * std::mem::size_of::<usize>());
    runner.register("vec", |data| {
        let vec = black_box(test_vec(data));
        // The return value of the function will be reported as the `OutputValue` 
        vec.len() as u64
    });
    runner.register("hashmap", move |data| {
        let map = black_box(test_hashmap(data));
        // The return value of the function will be reported as the `OutputValue` 
        map.len() as u64 * (std::mem::size_of::<usize>() + std::mem::size_of::<i32>()) as u64
    });
    runner.run();

}

fn main() {
    // Tuples of name and data for the inputs
    let data = vec![
        (
            "max id 100; 100 ids all the same",
            std::iter::repeat(100).take(100).collect(),
        ),
        ("max id 100; 100 ids all different", (0..100).collect()),
    ];
    bench_group(InputGroup::new_with_inputs(data));
}

```

### Example Output
```bash
cargo bench

turbo_buckets_vs_fxhashmap_full_unique
100k max id / 100k num elem
TurboBuckets           Memory: 786.4 KB     Avg: 2.1107 GiB/s (+0.19%)    Median: 2.1288 GiB/s (+0.69%)    [1.9055 GiB/s .. 2.1464 GiB/s]    
FxHashMap              Memory: 1.8 MB       Avg: 1.1116 GiB/s (-0.65%)    Median: 1.1179 GiB/s (-0.90%)    [1020.2 MiB/s .. 1.1363 GiB/s]    
500k max id / 500k num elem
TurboBuckets           Memory: 2.4 MB       Avg: 5.7073 GiB/s (-0.29%)    Median: 5.7633 GiB/s (-0.55%)    [5.1313 GiB/s .. 6.1104 GiB/s]    
FxHashMap              Memory: 14.2 MB      Avg: 521.50 MiB/s (-1.81%)    Median: 523.42 MiB/s (-1.75%)    [465.28 MiB/s .. 562.83 MiB/s]    
1m max id / 1m num elem
TurboBuckets           Memory: 4.5 MB       Avg: 6.2922 GiB/s (+5.48%)    Median: 6.3850 GiB/s (+6.56%)    [4.9580 GiB/s .. 6.7989 GiB/s]    
FxHashMap              Memory: 28.3 MB      Avg: 403.52 MiB/s (+0.00%)    Median: 396.74 MiB/s (+0.97%)    [355.83 MiB/s .. 473.37 MiB/s]    
```

### Peak Memory
To activate peak memory reporting, you need to wrap your allocator with the PeakMemAlloc and enable the PeakMemAllocPlugin (see example above).

While number of allocations are also interesting for performance analysis, peak memory will determine the memory requirements of the code.

### Perf Integration
Perf may run into limitations where all counters are reported as zero. https://github.com/jimblandy/perf-event/issues/2
Disabling the NMI watchdog should help:

`sudo sh -c "echo '0' > /proc/sys/kernel/nmi_watchdog"`

### TODO

- [ ] Improve the reporter api. Currently the reporter gets preaggregated data.

#### Maybe Later Features:
* Charts
* Auto comparison of Histograms (e.g. if a benchmark has several bands in which it operates, it would be nice to compare them)