SYSTEM DESIGNDesign a Key-Value Store (Redis)AmazonGoogleMicrosoft
TRAFFIC LEVEL
—/3
CONSTRAINTS
Target RPS1,000,000
p99 latency< 1ms
Replication factor3
Memory per node64 GB
Key sizeavg 64 bytes
Compute & Network
Load BalancerDistribute traffic
API GatewayEntry point / auth
API ServerBusiness logic
Worker NodeAsync processing
CDN EdgeGlobal cache
WebSocket GatewayPersistent connections
Data Stores
PostgreSQLRelational DB
MySQLRelational DB
CassandraWide-Column DB
DynamoDBNoSQL / Managed
S3 BucketObject storage
Queues & Cache
Redis CacheIn-memory store
KafkaEvent stream
ZookeeperCoordination
Specialized
Bloom FilterProbabilistic set
Rate LimiterThrottling
Geohash ServiceGeospatial index
Trie ServerPrefix search
APNS / FCMPush notifications
AggregatorBatch / roll-up
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🚨 INCIDENT
AmazonGoogleMicrosoft

Design a distributed key-value store that supports GET, PUT, DELETE with sub-millisecond latency for 1M RPS. Data must survive server failures and be partitioned across nodes. Support TTL and LRU eviction.

📥 Assigned to:You — Mid Engineer
SCALE LEVELS
1
10,000 RPS
Target: <5ms
2
100,000 RPS
Target: <2ms
3
1,000,000 RPS
Target: <1ms
GLOBAL SUCCESS RATE
100.0%
P99 LATENCY
45ms
Target: < 200ms
TOTAL RPS INGESTED0 / 11,000
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