Interview

 Q: When to use Parallel vs Async?

✅ Answer:

"Parallel is used for CPU-bound operations where computation is heavy,
whereas async/await is used for I/O-bound operations where the system waits for external resources like APIs or databases."

👉 Bangla:

"CPU heavy কাজ হলে Parallel, আর external wait থাকলে Async/Await ব্যবহার করি।"

Feature	Parallel	Async/Await
Type	CPU-bound	I/O-bound
Thread	Multiple threads	Non-blocking
Performance	Fast for heavy computation	Efficient for waiting
Use Case	Data processing	API/DB/File

 

Scenario 1: Employee Data Processing (CPU-Bound → Parallel)

Business Requirement

HR system-এ 500,000 employee records আছে।

প্রতিটি employee-এর জন্য:

• Salary calculation
• Tax calculation
• Bonus calculation

করতে হবে।

✅ CPU doing work → Parallel

Examples:

• Salary Calculation
• Report Generation
• Image Processing
• Data Transformation

---

✅ CPU waiting → Async/Await

Examples:

• API Call
• Database Query
• File Read/Write
• Azure Blob Storage Access