What to estimate?

QPS - queries per second

RPS - reads per second

WPS - writes per second

Peak QPS = QPS * 2 (usually)

RW - read write ratio

Message size - size of the message in bytes if not given

Read Throughput - RPS * message size = N bytes per second

Write Throughput - WPS* message size = N bytes per second

*Think about bandwidth

<aside> 💡 Throughput is how much data actually passed through and bandwidth is how much data CAN be passed through (network configuration) Ex: 1gbps network bandwidth can pass 125mb/s

</aside>

Storage - usually storage for N years

Replica storage - storage * 2-3 times

Cache storage - usually 20% of storage or so

Cache replica storage - cache storage * 2-3 times

Basic Numbers

seconds in a day - 24 * 60 * 60 = 86400, roughly 10^5

1 ASCI letter - 1 char

timestamp - 8 bytes (2^64)