Menene bambanci tsakanin blocking da non-blocking (sync da async) I/O?

Question

IT Interview Practice · Accepted Answer

**Blocking I/O yana dakatar da thread mai kira har sai aikin ya ƙare; non-blocking I/O yana dawowa nan da nan kuma yana barin thread ya yi wani aiki yayin da aikin ke ƙarewa.** Sync da async suna bayyana ra'ayi ɗaya a matakin API.

## Yadda yake aiki

- **Blocking / synchronous**: thread yana tsayawa a kan `read()` har sai bayanai sun iso. Mai sauƙi, amma thread yana zaune babu aiki dukan lokacin — don yi wa clients N masu jinkiri hidima kana buƙatar threads N.
- **Non-blocking / asynchronous**: kiran yana dawowa nan da nan; sakamako yana iso daga baya ta callback, promise, ko sanarwar event loop. Thread ɗaya na iya sarrafa dubunnan connections.

```text
Blocking:     ──[ wait for disk ]── (thread stuck, does nothing)
Non-blocking: ──▶ returns now; event loop notified when ready
```

## Misali

```js
// Blocking: nothing else runs until the file is read
const data = fs.readFileSync('big.txt');

// Non-blocking: thread keeps going; callback fires later
fs.readFile('big.txt', (err, data) => { /* handle later */ });
// or async/await on top of non-blocking primitives
const data2 = await fs.promises.readFile('big.txt');
```

## Me ya sa yake da muhimmanci

Wannan shine tushen servers masu scaling. Node.js da nginx suna sarrafa manyan ƙidayar connections a kan threads kaɗan daidai saboda I/O ba blocking ba ne — jira ba ya ɗaure thread. Yi amfani da blocking calls don sauƙi a scripts; yi amfani da non-blocking don sabis na network mai high-concurrency, kuma kada ka taɓa toshe event loop da aikin CPU mai nauyi.

Yadda yake aiki

Misali

Me ya sa yake da muhimmanci

Tambayoyi masu alaƙa