Bitcoin Miners Teach Pivotal a Lesson About Isolating Cloud Workloads

When Pivotal started offering free 60-day trials of its public Platform-as-a-Service cloud, giving people free data center infrastructure for Bitcoin mining wasn’t exactly what the company had in mind.

Of course, a free trial is a free trial and users are free to use it however they want to. The problem with Bitcoin-mining applications for Pivotal, however, was that these apps use very little memory and a lot of CPU horsepower, Mark Kropf, Cloud Foundry product manager at Pivotal, said.

Until recently, the company used to use the size of memory a workload consumes to charge for Pivotal Web Services, regardless of the CPU resources involved. Its free trial originally gave a user 2GB of memory and unlimited CPU.

With this approach, Pivotal very quickly ended up with lots of Bitcoin mining applications – which only require about 8 megabytes of memory – running in its cloud and hogging a massive amount of the infrastructure’s compute capacity, Kropf said.

To stop the problem, Pivotal changed the model, tying CPU capacity to memory so that the amount of memory an application uses dictates the amount of physical CPU capacity available to it. And it worked: the miners went away. “That [change] made it financially not viable for Bitcoin miners,” Kropf said.

To be sure, Pivotal does not view Bitcoin mining as a workload that should be kept away from its cloud at all costs. More than anything, the experience taught the company a lesson about isolating workloads in its cloud to prevent applications from hogging CPU capacity to a point where they harm other applications. “We are able to better segregate workload between apps,” Kropf said.

Pivotal Web Services is based on Cloud Foundry, an open source PaaS technology the company spearheaded and continues to be heavily involved in. Like Amazon Web Services’ Elastic Beanstalk or Salesforce’s Heroku, it enables developers to easily deploy and scale applications in the cloud.

Public cloud is only one of the ways Bitcoin miners deploy their workloads. Because it requires a lot of processing horsepower, Bitcoin mining has become a rapidly growing niche market for data center service providers.

A company called KnC Miner, for example, is building a 10 megawatt data center in Sweden where it will provide dedicated servers for the sole purpose of mining digital currency. C7 Data Centers has about 4.5 MW of data center capacity dedicated to Bitcoin mining and companies in the cryptocurrency ecosystem.