Numbers To Know medium
You have 10 Million Daily Active Users (DAU). Each user makes average 10 requests per day. What is the average QPS?
- A approximately 1,150 QPS
- B approximately 10,000 QPS
- C approximately 100,000 QPS
- D approximately 500 QPS
Answer: A. approximately 1,150 QPS
To find the average QPS (Queries Per Second), first calculate the total daily volume: 10 Million users $\times$ 10 requests = 100 Million total requests. Dividing this by the number of seconds in a day (~100,000 for estimation, or precisely 86,400) gives you ~1,157 requests per second. While this 'average load' is easy to calculate, an engineer must always design for 'Peak Load'. In most consumer apps, traffic spikes during evening hours can be 2 to 5 times the average. Designing for a 1,150 QPS average likely means your system must be able to handle at least 3,000 to 5,000 QPS without breaking.
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