| 12 | }); |
| 13 | |
| 14 | async function main({ n, bufferSize }) { |
| 15 | let enqueued = 0; |
| 16 | |
| 17 | const rs = new ReadableStream({ |
| 18 | start(controller) { |
| 19 | // Pre-fill the buffer |
| 20 | for (let i = 0; i < bufferSize; i++) { |
| 21 | controller.enqueue('a'); |
| 22 | enqueued++; |
| 23 | } |
| 24 | }, |
| 25 | pull(controller) { |
| 26 | // Refill buffer when pulled |
| 27 | const toEnqueue = Math.min(bufferSize, n - enqueued); |
| 28 | for (let i = 0; i < toEnqueue; i++) { |
| 29 | controller.enqueue('a'); |
| 30 | enqueued++; |
| 31 | } |
| 32 | if (enqueued >= n) { |
| 33 | controller.close(); |
| 34 | } |
| 35 | }, |
| 36 | }, { |
| 37 | // Use buffer size as high water mark to allow pre-buffering |
| 38 | highWaterMark: bufferSize, |
| 39 | }); |
| 40 | |
| 41 | const reader = rs.getReader(); |
| 42 | let x = null; |
| 43 | let reads = 0; |
| 44 | |
| 45 | bench.start(); |
| 46 | while (reads < n) { |
| 47 | const { value, done } = await reader.read(); |
| 48 | if (done) break; |
| 49 | x = value; |
| 50 | reads++; |
| 51 | } |
| 52 | bench.end(reads); |
| 53 | console.assert(x); |
| 54 | } |