std/bench

9 exports, from std/bench.vyrn.

The runtime the vyrn bench transform links against. Only the synthesized bench main imports it, so its clock use never reaches a run or build.

Dependencies

The import graph shows the whole library.

Imports: time json jsonread
Imported by: no other std module

minOf fn

fn minOf(xs: Array<Int64>) -> Int64

The minimum of a non-empty sample array.

mean fn

fn mean(xs: Array<Int64>) -> Int64

The truncating integer mean of a non-empty sample array.

median fn

fn median(xs: Array<Int64>) -> Int64

The median (upper-middle element) of a non-empty sample array.

formatDuration fn

fn formatDuration(ns: Int64) -> String

A nanosecond duration in human units: ns below one microsecond, then microseconds, ms or s with two fractional digits.

padRight fn

fn padRight(s: String, width: Int64) -> String

Right-pads s with spaces to width bytes; never truncates.

BenchResult type

type BenchResult = {
    name: String,
    minNs: Int64,
    medianNs: Int64,
    meanNs: Int64,
    samples: Int64,
    iters: Int64,
}

One bench's per-iteration statistics in nanoseconds, and the sample and iteration counts. Compare regressions on minNs, the least noisy.

benchMeasure fn

fn benchMeasure(name: String, body: fn() -> Unit) -> BenchResult

Times one bench body and returns its statistics:

1. warm up for about 50 ms, discarding results;
2. double the per-sample iteration count until one sample takes 1 ms;
3. collect samples until at least 31 and 500 ms, capped at 2 s;
4. compute min, median and mean per-iteration time.

The body keeps its work alive with blackBox, so the compiler cannot delete it between iterations.

benchOne fn

fn benchOne(name: String, width: Int64, body: fn() -> Unit)

Times one bench body and prints its report line. width is the label column width, computed from every bench name.

benchJson fn

fn benchJson(results: Array<BenchResult>, backend: String, opt: String) -> String

The --json bench report: compact, benches in declaration order, every number an integer: { backend, opt, benches: [ { name, minNs, medianNs, meanNs, samples, iters } ] }.

Tests

5 test blocks in std/bench.vyrn. CI runs all of them.

Test names

formatDuration picks human units
median and mean over a small sample
padRight fills to width and never truncates
benchJson emits the locked schema in stable order
benchJson output round-trips through parseJson

Examples

No example program imports this module.