issue-25028.js

'use strict';
const fs = require('fs').promises;
const child_process = require('child_process');

const kPIDSpace = 100000;
const kSetupParallelism = 100;

async function createUnwritableFile(filename) {
  try {
    await fs.unlink(filename);
  } catch {}
  // Mode 0 means no access at all.
  await fs.writeFile(filename, '', { mode: 0 });
}

(async function() {
  // Saturate /tmp with unwritable files of the name format /tmp/perf-${pid}.map
  for (let i = 0; i < kPIDSpace; i += kSetupParallelism) {
    const filePromises = [];
    for (let j = i; j < i + kSetupParallelism; j++) {
      const filename = `/tmp/perf-${j}.map`;
      filePromises.push(createUnwritableFile(filename));
    }
    await Promise.all(filePromises);
  }

  child_process.execFileSync(process.execPath, ['--perf-basic-prof', '-e', '']);
})();