Live architecture

How PulseRooms Scales

Pulled live from Amazon DynamoDB. Write sharding prevents hot partitions; Global Tables push data closer to every player on earth.

us-east-1

Region

Global Tables enabled

On-Demand

Billing Mode

No capacity planning

Enabled

DynamoDB Streams

NEW_AND_OLD_IMAGES

3 replicas

Global Tables

us-east-1, eu-west-1, ap-northeast-1

Global Secondary Indexes

GSI2GSI2PK · GSI2SK

Season-level aggregated rankings sorted by cumulative score

GSI1GSI1PK · GSI1SK

Write-sharded room leaderboard — fan-out writes across shards, scatter-gather for reads

Write-Shard Distribution

LIVE · 157 players
Shard 0
18
Shard 1
14
Shard 2
20
Shard 3
18
Shard 4
11
Shard 5
15
Shard 6
15
Shard 7
19
Shard 8
9
Shard 9
18

Writes distributed across 10 shards via SHARD#live-1#hash(playerId) % 10. A scatter-gather query reads all 10 shards and merges the top-K.

Load-Test Proof — in-region Lambda fleet

Retries off so throttles surface. Single partition vs 10 shards, measured on real DynamoDB.

1,262 ms

Single-partition p99

Hot partition, matched load

154 ms

Sharded p99

10-shard scatter-gather

47,115

Throttles (single, sustained)

Sharded: 0