अनुमान र क्षमता योजना — अपेक्षित लोड, डेटा भोल्यूम, र संसाधन आवश्यकताहरू गणना गर्ने — सिस्टम डिजाइनको एक महत्त्वपूर्ण भाग हो। रफ "back-of-the-envelope" गणनाहरूले डिजाइन निर्णयहरूलाई सूचित गर्छन् (कति स्केल गर्ने, कस्तो संसाधनहरू आवश्यक छन्) र डिजाइन अन्तर्वार्तामा सामान्य छन्।
अनुमान किन महत्त्वपूर्ण छ
Estimating scale informs DESIGN decisions:
→ how many servers? how much storage? what database? do you need sharding/caching?
→ understanding the SCALE (small vs massive) shapes the whole design
→ rough numbers guide whether/how to scale (don't over- or under-engineer)
के अनुमान गर्ने (back-of-the-envelope)
✓ TRAFFIC → users, requests/sec (QPS); read vs write ratio (e.g. 100:1 reads:writes)
→ peak vs average (design for peak); daily active users → requests
✓ STORAGE → data size per item × volume × growth over time → total storage (and growth rate)
✓ BANDWIDTH → data transferred per second (request size × QPS)
✓ MEMORY → cache size needed (e.g. cache the hot 20% of data)
→ rough estimates (order of magnitude) → good enough to inform design
