Scalability - Harvard lecture

https://www.youtube.com/watch?v=-W9F__D3oY4

Vertical Scaling

  • CPU: cores, L2 cache

  • Disk

  • RAM

Horizontal Scaling

  • multiple servers

  • then we need to distribute requests - load balancer

load balancer

  • round robin is not so good if there's some heavy users in specific server

  • RAID (redundant array of independent disks) - RAID works by placing data on multiple disks and allowing input/output (I/O) operations to overlap in a balanced way, improving performance. Because the use of multiple disks increases the mean time between failures (MTBF), storing data redundantly also increases fault tolerance.

  • Software: ELB, HAProxy

  • Hardware

Sticky sessions - 断电之类的 single failure

  • shared storage

  • cookies

Caching

  • .html

  • MySQL Query Cache

  • memcached

Replication

  • Master-slave

  • Master-master

PreviousKey Characteristics of Distributed SystemsNextScalability for Dummies - Part 1: Clones

Last updated