Where is my post
Difficulty 2 of 5
A user saves a post, then reads through a replica that is two seconds behind. No user may read a version older than their own completed write. Keep p99 below 100 ms.
0:00. A user saved a post, then could not see it. Graph: replica lag stays near 2 s after every write.
W 3 + R 3 of 5 · every read sees the last write
Goals and limits
- Missing own writes
- none
- p99 latency
- under 100 ms
- Monthly cost
- under 100 USD/mo
- Parts you can add
- Postgres
- Part limit
- 16
- Edit limit
- 3
- Traffic
- 1,000 req/s
Concepts
How players did
Player results load from the server.