Refactor benchmark script (#6376)

* Add timer setting

* Setup benchmark code

* Setup memory benchmark

* Add compare function

* Add result preview

* Setup results preview

* Simplify script for CI

* Update CI

* Cleanup

* Temp remove fork guard

* Fix stuff

* Fix again

* Fix quotes

* Fix multiline output

* Simplify title

* Fix memory numbers

* Remove astro bin dir

* Fix gc

* Add repo guards

* Fix wrong call

* Set max space size

* Remove guard

* Bump memory a bit

* Organize neatly

* Update readme

* Try large md

* Try no gc

* Revert markdown and gc changes

* Test sha

* Try ref

* Try 128mb

* Set 256

* Add guard

* Apply suggestions from code review

Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca>

* Add docs comment

---------

Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca>

1 files changed, 58 insertions, 0 deletions

diff --git a/benchmark/bench/memory.js b/benchmark/bench/memory.js
new file mode 100644
index 000000000..1f0d8ab8b
--- /dev/null
+++ b/benchmark/bench/memory.js
@@ -0,0 +1,58 @@
+import fs from 'fs/promises';
+import { fileURLToPath } from 'url';
+import { execaCommand } from 'execa';
+import { markdownTable } from 'markdown-table';
+import { astroBin } from './_util.js';
+
+/** @typedef {Record<string, import('../../packages/astro/src/core/config/timer').Stat>} AstroTimerStat */
+
+/** Default project to run for this benchmark if not specified */
+export const defaultProject = 'memory-default';
+
+/**
+ * @param {URL} projectDir
+ * @param {URL} outputFile
+ */
+export async function run(projectDir, outputFile) {
+	const root = fileURLToPath(projectDir);
+	const outputFilePath = fileURLToPath(outputFile);
+
+	console.log('Building and benchmarking...');
+	await execaCommand(`node --expose-gc --max_old_space_size=256 ${astroBin} build`, {
+		cwd: root,
+		stdio: 'inherit',
+		env: {
+			ASTRO_TIMER_PATH: outputFilePath,
+		},
+	});
+
+	console.log('Raw results written to', outputFilePath);
+
+	console.log('Result preview:');
+	console.log('='.repeat(10));
+	console.log(`#### Memory\n\n`);
+	console.log(printResult(JSON.parse(await fs.readFile(outputFilePath, 'utf-8'))));
+	console.log('='.repeat(10));
+
+	console.log('Done!');
+}
+
+/**
+ * @param {AstroTimerStat} output
+ */
+function printResult(output) {
+	return markdownTable(
+		[
+			['', 'Elapsed time (s)', 'Memory used (MB)', 'Final memory (MB)'],
+			...Object.entries(output).map(([name, stat]) => [
+				name,
+				(stat.elapsedTime / 1000).toFixed(2),
+				(stat.heapUsedChange / 1024 / 1024).toFixed(2),
+				(stat.heapUsedTotal / 1024 / 1024).toFixed(2),
+			]),
+		],
+		{
+			align: ['l', 'r', 'r', 'r'],
+		}
+	);
+}