AdRoll’s leadership estimates that the company has been able to reduce IT costs well below industry benchmarks for companies processing similar sets of data on premises. “By leveraging the AWS global infrastructure and services, we’ve been able to reduce fixed costs by 75 percent and annual operational costs by 83 percent,” says Volonghi.

AdRoll uses a combination of On-Demand, Reserved, and Spot Instances to operate the RTB platform. While most of AdRoll’s tasks run on On-Demand and Reserved Instances, the company uses Spot Instances to run big data jobs on Hadoop clusters. Analytics tasks, for example, require thousands of machines in an unpredictable quantity. By taking advantage of the Spot market for intensive, non-time-critical computation processes, AdRoll is able to reduce costs by nearly 80 percent compared to On-Demand Instances.

“We run the RTB platform on more than 2,500 machines, approximately eight hours a day globally, at a cost of less than $0.05 per day per machine,” says Volonghi. “If we wanted to replicate our AWS environment on premises, we would have to operate four data centers with on-call staff in each location, provision nearly 1,000 machines in each location, add an additional 10-20 percent capacity for cold storage, and develop code for auto-scaling and a common API.”

AdRoll estimates that it would need at least 20 full-time engineers to effectively manage the physical environment:

• 8 full-time employees on call across four different data centers (two in each location for redundancy)
• 1 product manager for auto-scaling and API management
• 5 engineers to develop and maintain auto-scaling across the infrastructure
• 5 engineers to maintain Cassandra installation instead of DynamoDB
• 1 engineering manager

The overall annual staffing costs, with an average engineering salary of $150,000, would be $3 million.

Using Amazon S3 for storage helps the company reduce storage and management costs. AdRoll’s Amazon S3 buckets generate as much traffic as some of the most visited properties on the web. “We process the same amount of data that a storage company does, but we don’t need the same level of engineering resources dedicated to managing that storage,” says Volonghi. “We can handle this large, complex task with ease and minimal burden. For example, now that we’re running on AWS, we can manage the RTB workload successfully using just two engineers instead of eight.” AdRoll deployed a 180 TB storage environment using Amazon S3 for well under 10 percent of the cost of an on-premises equivalent.