Scaling

What to do when one machine stops being enough, and what breaks the moment there are two.

1. 01

   Vertical vs Horizontal Scaling

   0/4

   Scale up (bigger machine) vs scale out (more machines).

   1. Scaling Up: The Bigger Box2 min
   2. Scaling Out: More Boxes2 min
   3. What Breaks When You Go Horizontal2 min
   4. Choosing in an Interview2 min
2. 02

   Load Balancing

   0/4

   Distribute traffic across servers so no single machine is overwhelmed.

   1. What a Load Balancer Does2 min
   2. Picking an Algorithm6 min
   3. L4 vs L73 min
   4. Health Checks and Failure Handling2 min
3. 03

   Database Replication

   0/4

   Copy data across multiple DB nodes for reads and high availability.

   1. Leader-Follower Basics2 min
   2. Sync vs Async Replication2 min
   3. Replication Lag in Practice3 min
   4. Failover and Multi-Leader3 min
4. 04

   Database Sharding

   0/4

   Horizontally partition data across multiple DB instances by shard key.

   1. Why Shard, and Why Wait2 min
   2. Picking a Shard Key3 min
   3. Resharding Pain3 min
   4. Living with Cross-Shard Queries3 min