Function darwinMemoryAvailable

src/resolution/memory-budget.ts:87–107

()

 * once per call (pool sizing runs it once per init; a few ms). Never throws.
 */
export function darwinMemoryAvailable(): number | null {
  if (process.platform !== 'darwin') return null;
  try {
    const out = execFileSync('/usr/bin/vm_stat', { encoding: 'utf8', timeout: 2000 });
    const pageMatch = /page size of (\d+) bytes/.exec(out);
    const pageSize = pageMatch ? Number.parseInt(pageMatch[1]!, 10) : 16384;
    const count = (label: string): number => {
      const m = new RegExp(`^${label}:\\s+(\\d+)`, 'm').exec(out);
      return m ? Number.parseInt(m[1]!, 10) : 0;
    };
    const pages =
      count('Pages free') +
      count('Pages inactive') +
      count('Pages speculative') +
      count('Pages purgeable');
    const bytes = pages * pageSize;
    return bytes > 0 && Number.isFinite(bytes) ? bytes : null;
  } catch {
    return null;
  }
}

/**
 * The budget pool sizing divides: the smaller of system free memory and the