App Containers Begin to Scale
Real-world assessments about the adoption of Docker application containers in production are surfacing as users deploy the technology to boost utilization of datacenter resources and accelerate delivery of a range of enterprise applications.
According to a Docker usage report released this week, the median number of containers per server has jumped 50 percent to 15 over the past year. In one instance, the report released by the container monitoring vendor Sysdig found one user running 154 containers on a single host. “That’s a lot of containers,” noted the usage story released on Tuesday (May 29).
Docker remains by far the leading container runtime, accounting for 83 percent of containers in production. The usage report notes however that the micro-services landscape is evolving with Red Hat’s (NYSE: RHT) January acquisition of No. 2 container runtime CoreOS. Along with a healthy increase in users of the CoreOS runtime dubbed “rkt,” (12 percent), the report notes that the Open Container Initiative is establishing industry standards for a container runtime and image specifications along with promoting container portability.
The upshot is that “customers have a greater comfort level with using ‘non-Docker’ solutions in production,” the survey noted.
Among the most popular applications running in containers are Java virtual machines and a growing roster of open-source platforms such as the etcd distributed key value store promoted by CoreOS as a way to store data across a cluster of virtual machines.
Meanwhile, databases such as MongoDB (NASDAQ: MDB) and PostgreSQL are increasingly being supported in container infrastructure, signaling a shift to stateful services running in containers. “The ephemeral nature of containers left many concerned about running services that collect valuable corporate data in containers,” the usage study noted. “The concern appears to be easing as the data suggests customers are beginning to move to environments completely driven by containers.”
As container technology matures, more enterprises are using the Kubernetes orchestrator to direct traffic. Nearly all key cloud players have added support for Kubernetes, as have container specialists like Docker and Mesosphere, underscoring the reality that the cluster orchestrator pioneered by Google (NASDAQ: GOOGL) has emerged as a de facto industry standard.
Indeed, Kubernetes accounted for the lion’s share (82 percent) of open source orchestration distributions, well ahead of Red Hat’s OpenShift platform (14 percent).
The usage study also found that container cluster size often influences the choice of an orchestrator, with Docker’s Swarm orchestrator at the low end, Kubernetes in the middle and Mesosphere’s Marathon and “Datacenter Operating System” handling the most clusters of 50 or more containers.
“Mesos clusters are typically enterprise-scale,” the survey noted.
With applications containers now established in production, DevOps teams are seen embracing micro-services platforms based on stateless and, gradually, stateful services such as databases. “New approaches are maturing and helping organizations develop applications more quickly,” the Sysdig survey concluded.