Cloud bursting for fun and profit…own the base, rent the spike.
eBay 2B page views/day 6000 application servers 9PB of data.
Cloud bursting: control costs and increase efficiency.
2000 servers provisioned at a fixed cost but only 300-1600 used at any given point of the day. A lot of “whitespace” or excess capacity.
How can we remove the peaks? Time shifting the workload helps a little bit, bringing us down to about 800 servers required.
Financial model structure: take the hourly demand in average TPS and max TPS per CU to get the hourly computing units required (CUs). Take the number of CUs in the internal cloud and the hourly cost, plus the hourly CUs in the extermal cloud, you get total hourly cost.
Cost benefit analysis shows that an external cloud at 4x the cost of the internal cloud still yields economic benefits in dealing with the spikes.
If the cost of the cloud is half of the internal cloud then it makes no sense to run anything internally.
In between is the interesting area where we need to make hard choices.
Cloud bursting is very interesting to eBay, allowing us to cut costs by at least 25%.
Lower the investment in infrastructure to focus on the business intelligence.