Giant Scale Services

Summary

• Generic Service Model of Giant Scale Services
• DQ Principle
• Online Evaluation and Growth

Generic Service Model of Giant Scale Services

Load balancer in front of server, each with data store

DQ Principle

yield = completed / offered

harvest = viewed / full

DQ means Data Rate per Query * Data Served

• DQ is constant
  • Increase D by Decreasing Q

DQ is a better metric than uptime

Online Evaluation and Growth

How to do you upgrade servers without bringing down the cluster?

Fast

• offpeak (e.g. use diurnal server property)

Rolling upgrade

• one by one

Big Flip

• Half the nodes at once

DQ Loss is same for all

• DQ * upgrade time per node * number of nodes