SEATTLE -- The Docker platform for Linux containers is growing fast. Docker's momentum is big. But is it getting a little too big? This was the lingering question here at DockerCon this week.

In speeches here over two days, Docker CEO Ben Golub and Docker Founder and CTO Solomon Hykes did not appear to have mercantilist attitudes. They stressed the warm and fuzzy -- the role of Docker in the development and operations community (DevOps) to simplify the building, implementation, and migration of applications across infrastructure, whether it be traditional infrastructure or the cloud.

"It's everything you need to go from simple, containerized development to a whole live system that can receive anything from anywhere, anytime that can span multiple service providers and survive hardware failures," said Hykes, looking trim and peppy in the uniform of the DevOps crowd -- jeans and T-shirt.

Despite the growing success of Docker -- the company is now understood to have a multi-billion dollar valuation because of its expanding use by DevOps teams -- there is some anxiety among its technology partners that Docker will wield its growing power to rule the container management space. Even though many of Docker's tools are open source, its management platform is a proprietary software product that the company is now monetizing with large services contracts.

Docker announced this week that it is including orchestration and security tools with the subtly named 1.12 release of its platform (couldn't they have least named it 1.2?). This was supposed to freak out a bunch of the VC-funded container startups that are providing orchestration and security tools.

But speaking with many attendees of DockerCon, I found the anxiety either downplayed -- or hidden -- as container technologists said there is plenty of room for partners -- as witness by the more than 50 show sponsors and exhibitors.

For example, officials at Apcera, the container management company majority owned by Ericsson, pointed out that the new Docker orchestration features only work for single application microservices and are primarily targeted at software-as-a-service (SaaS) providers. Apcera positions itself for more sophisticated purveyors of multiple apps in large enterprises.

"A highly available global infrastructure needs the ability to address many applications," said Josh Ellithorpe, lead software architect with Apcera.

Sheng Liang, CEO of container management startup Rancher, said many container systems will continue to co-exist, including Docker, Kubernetes, and Mesos. "Not everybody that puts containers in production chooses Kubernetes, some people use Swarm," said Liang. "We support all of them -- Swarm, Kubernetes and Mesos." (Swarm is Docker's application orchestration product, while Kubernetes and Mesos are open-source tools with similar goals.)

That did not keep some tongues a wagging. Several participants noticed the absence of Google at DockerCon, while Amazon Web Services (AWS) and Microsoft's Azure -- the two other monsters in the cloud services market -- continue to support the show. Google, which invented Kubernetes and then introduced it as open-source, could see Docker's move into orchestration as competing technology.

But it's doubtful that Docker is going to launch a suite of tools as deep as the entire container infrastructure ecosystem, as we described in our Inside the Linux Container Ecosystem Report.

Take a look at the IP networking market, for example, as an analogy. Decades after IP networking was invented, dozens of vendors are selling IP-based routing, switching, and management tools, both in hardware and software. The container market must be large enough to support many dozens of companies providing tools to manage microservices applications.

One thing is clear: The audience here was mesmerized by the rapid growth of the Docker platform and the way it has brought simplicity to an otherwise chaotic world of wrangling microservices. As reported here, Datadog found that Docker's market share has increased 30 percent. And there are the numbers of DockerCon itself: It has ramped from 500 attendees to 4,000 people in three years, making it a destination technology show reminiscent of the early days of VMWorld.

Which brings us to the next question: How big can Docker get? In a lunch meeting with press and analysts, Docker CEO Golub said that Docker's addressable market is on par with VMware's addressable market in virtualization -- at least tens of billions of dollars. Although Golub stated that Docker is not yet profitable, he said the last series D venture round -- which brought Docker total funding to $185 million invested as well as Unicorn status -- should be enough to get it to profitability. "Hopefully we won't have to raise any more money."

Not bad for a 250-person company.

"It shows us how fast this thing is moving," said Nand Mulchandani, vice president of marketing development with Citrix, which is so excited about containers that it's re-launching its Netscaler product as a container native application. "Here we are at 4,000 people in year three ... it's insane."