### [`BenchEvent`](https://tinylibs.github.io/tinybench/types/BenchEvent.html)

## Timestamp Providers

Tinybench can utilize different timestamp providers for measuring time intervals.

By default it uses `performance.now()`.

The `timestampProvider` option can be set when creating a `Bench` instance. It

accepts either a `TimestampProvider` object or shorthands for the common

providers `hrtimeNow` and `performanceNow`.

If you use `bun` runtime, you can also use `bunNanoseconds` shorthand.

You can set the `timestampProvider` to `auto` to let Tinybench choose the most

precise available timestamp provider based on the runtime.

```ts

import { Bench } from 'tinybench'

const bench = new Bench({

timestampProvider: 'hrtimeNow' // or 'performanceNow', 'bunNanoseconds', 'auto'

})

```

If you want to provide a custom timestamp provider, you can create an object that implements

the `TimestampProvider` interface:

```ts

import { Bench, TimestampProvider } from 'tinybench'

// Custom timestamp provider using Date.now()

const dateNowTimestampProvider: TimestampProvider = {

name: 'dateNow', // name of the provider

fn: Date.now, // function that returns the current timestamp

toMs: ts => ts, // convert the timestamp to milliseconds

fromMs: ts => ts // convert milliseconds to the format used by fn()

}

const bench = new Bench({

timestampProvider: dateNowTimestampProvider

})

```

You can also set the `now` option to a function that returns the current timestamp.

It will be converted to a `TimestampProvider` internally.

```ts

import { Bench } from 'tinybench'

const bench = new Bench({

now: Date.now

})

```

## Async Detection

Tinybench automatically detects if a task function is asynchronous by

await bench.run()

```

## Convert task results for `console.table()`

You can convert the benchmark results to a table format suitable for

`console.table()` using the `bench.table()` method.

```ts

const table = bench.table()

console.table(table)

```

You can also customize the table output by providing a convert-function to the `table` method.

```ts

import { Bench, type ConsoleTableConverter, formatNumber, mToNs, type Task } from 'tinybench'

/**

* The default converter function for console.table output.

* Modify it as needed to customize the table format.

*/

const defaultConverter: ConsoleTableConverter = (

task: Task

): Record<string, number | string> => {

const state = task.result.state

return {

'Task name': task.name,

...(state === 'aborted-with-statistics' || state === 'completed'

? {

'Latency avg (ns)': `${formatNumber(mToNs(task.result.latency.mean))} \xb1 ${task.result.latency.rme.toFixed(2)}%`,

'Latency med (ns)': `${formatNumber(mToNs(task.result.latency.p50))} \xb1 ${formatNumber(mToNs(task.result.latency.mad))}`,

'Throughput avg (ops/s)': `${Math.round(task.result.throughput.mean).toString()} \xb1 ${task.result.throughput.rme.toFixed(2)}%`,

'Throughput med (ops/s)': `${Math.round(task.result.throughput.p50).toString()} \xb1 ${Math.round(task.result.throughput.mad).toString()}`,

Samples: task.result.latency.samplesCount,

}

: state !== 'errored'

? {

'Latency avg (ns)': 'N/A',

'Latency med (ns)': 'N/A',

'Throughput avg (ops/s)': 'N/A',

'Throughput med (ops/s)': 'N/A',

Samples: 'N/A',

Remarks: state,

}

: {

Error: task.result.error.message,

Stack: task.result.error.stack ?? 'N/A',

}),

...(state === 'aborted-with-statistics' && {

Remarks: state,

}),

}

}

const bench = new Bench({ name: 'custom table benchmark', time: 100 })

// add tasks...

console.table(bench.table(defaultConverter))

```

## Retaining Samples

By default Tinybench does not keep the samples for `latency` and `throughput` to

}, { retainSamples: true })

```

## Timestamp Providers

Tinybench can utilize different timestamp providers for measuring time intervals.

By default it uses `performance.now()`.

The `timestampProvider` option can be set when creating a `Bench` instance. It

accepts either a `TimestampProvider` object or shorthands for the common

providers `hrtimeNow` and `performanceNow`.

If you use `bun` runtime, you can also use `bunNanoseconds` shorthand.

You can set the `timestampProvider` to `auto` to let Tinybench choose the most

precise available timestamp provider based on the runtime.

```ts

import { Bench } from 'tinybench'

const bench = new Bench({

timestampProvider: 'hrtimeNow' // or 'performanceNow', 'bunNanoseconds', 'auto'

})

```

If you want to provide a custom timestamp provider, you can create an object that implements

the `TimestampProvider` interface:

```ts

import { Bench, TimestampProvider } from 'tinybench'

// Custom timestamp provider using Date.now()

const dateNowTimestampProvider: TimestampProvider = {

name: 'dateNow', // name of the provider

fn: Date.now, // function that returns the current timestamp

toMs: ts => ts, // convert the timestamp to milliseconds

fromMs: ts => ts // convert milliseconds to the format used by fn()

}

const bench = new Bench({

timestampProvider: dateNowTimestampProvider

})

```

You can also set the `now` option to a function that returns the current timestamp.

It will be converted to a `TimestampProvider` internally.

```ts

import { Bench } from 'tinybench'

const bench = new Bench({

now: Date.now

})

```

## Aborting Benchmarks

Tinybench supports aborting benchmarks using `AbortSignal` at both the bench and task levels: