| 14 | }); |
| 15 | |
| 16 | function main({ n, type }) { |
| 17 | let fd; |
| 18 | |
| 19 | const tmpfile = { name: tmpdir.resolve(`.existing-file-${process.pid}`), |
| 20 | len: bufferSize * n }; |
| 21 | |
| 22 | |
| 23 | tmpfile.contents = Buffer.allocUnsafe(tmpfile.len); |
| 24 | |
| 25 | for (let offset = 0; offset < tmpfile.len; offset += sectorSize) { |
| 26 | const fillByte = 256 * Math.random(); |
| 27 | const nBytesToFill = Math.min(sectorSize, tmpfile.len - offset); |
| 28 | tmpfile.contents.fill(fillByte, offset, offset + nBytesToFill); |
| 29 | } |
| 30 | |
| 31 | fs.writeFileSync(tmpfile.name, tmpfile.contents); |
| 32 | |
| 33 | switch (type) { |
| 34 | case 'existing': |
| 35 | fd = fs.openSync(tmpfile.name, 'r', 0o666); |
| 36 | break; |
| 37 | case 'non-existing': |
| 38 | fd = 1 << 30; |
| 39 | break; |
| 40 | default: |
| 41 | new Error('Invalid type'); |
| 42 | } |
| 43 | |
| 44 | const buffer = Buffer.alloc(bufferSize); |
| 45 | |
| 46 | bench.start(); |
| 47 | for (let i = 0; i < n; i++) { |
| 48 | try { |
| 49 | fs.readSync(fd, buffer); |
| 50 | } catch { |
| 51 | // Continue regardless of error. |
| 52 | } |
| 53 | } |
| 54 | bench.end(n); |
| 55 | |
| 56 | if (type === 'existing') fs.closeSync(fd); |
| 57 | } |