Simulation Lab

Bad key, sharded key, and regional rollup design

The lab writes representative telemetry samples, then extrapolates hot-partition risk, WCU pressure, consistency risk, and readiness for the 1M-user Global Trivia Game target.

Scenario controls

1M users, 50k concurrent, US + EU, leaderboard pressure

Simulated users

Peak concurrent

50K

Sample events

1,200

Extrapolated EPS

8,000

Active run

Global Trivia Game - regional rollup projection design

Regional rollups split live writes by region, game shard, and leaderboard bucket while publishing a windowed global projection.

readiness

Hot partition risk

Consistency score

Cost score

Hot partition heatmap

Logical partition pressure

Jun 29, 11:54 PM

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What-if shard count estimator

Peak hot key WCU/s

200

Safety WCU target

700

Minimum shards

Recommended shards

Event stream

READ_LEADERBOARD

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Hot key findings

REGION#US#GAME#trivia-finals#SHARD#0

low

200 estimated WCU/s. Keep shard count tied to estimated peak WCU and monitor per-shard skew.

REGION#EU#GAME#trivia-finals#SHARD#5

low

200 estimated WCU/s. Keep shard count tied to estimated peak WCU and monitor per-shard skew.

REGION#US#GAME#trivia-finals#SHARD#16

low

193 estimated WCU/s. Keep shard count tied to estimated peak WCU and monitor per-shard skew.

REGION#US#GAME#trivia-finals#SHARD#30

low

187 estimated WCU/s. Keep shard count tied to estimated peak WCU and monitor per-shard skew.

REGION#EU#GAME#trivia-finals#SHARD#31

low

187 estimated WCU/s. Keep shard count tied to estimated peak WCU and monitor per-shard skew.

REGION#EU#GAME#trivia-finals#SHARD#17

low

187 estimated WCU/s. Keep shard count tied to estimated peak WCU and monitor per-shard skew.

REGION#EU#GAME#trivia-finals#SHARD#15

low

187 estimated WCU/s. Keep shard count tied to estimated peak WCU and monitor per-shard skew.

REGION#US#GAME#trivia-finals#SHARD#18

low

180 estimated WCU/s. Keep shard count tied to estimated peak WCU and monitor per-shard skew.