Expert
Read locally, write home
A Virginia retailer opens in Singapore. By law its orders must be stored in its Virginia database, so today every Singapore request crosses the Pacific, about 220 ms there and back. Make the store feel local in Singapore: fast pages, instant order confirmation, and every order in Virginia within half a minute.
Product pages are read far more often than they change, and most readers want the same products. The order database stays in Virginia and cannot move. An order may be confirmed as "received" before it reaches Virginia.
What your design must achieve
- Mean latency < 60 ms
- Writes p99 < 150 ms
- Availability ≥ 99.9 %
- Worst queue lag < 30 s
- Duplicated side effects = 0