DigitalOcean is a different kind of cloud supplier. It's added nearly two terabytes of solid state disks (actually 1,920 GBs) to each of its cloud hosts, letting customers spin up a server in 55 seconds.

And that seems to score with Ruby developers, a core customer group who like to see their Rails applications running with the click of mouse. Digital Ocean has also made it easy to deploy a server through its Web-based management console.

When Ronald van Woensel, a veteran user of Amazon Web Services, did a benchmark workload with DigitalOcean, he found that it ran slower than another startup he was testing, but faster than Amazon. "DigitalOcean is about half the speed of Linode, in spite of their fast SSD disks. But they are still six times faster than Amazon," he concluded in a July 2 blog on his benchmark, which was picked up and published on Hacker News.

That may explain why Internet research and security company Netcraft reports that DigitalOcean has grown extraordinarily over the past six months. In December 2012, after a year of operation, it ranked 568th in the world among hosting providers. By the end of June 2013, it had moved up to 72nd, according to Netcraft. It also increased its number of servers from 100 to 7,000. Only Amazon.com, Chinese search engine Alibaba, and German hosting and co-location firm Hetzner Online AG added more computers to their operations than DigitalOcean, Netcraft said.

[ Want to learn more about how DigitalOcean is impacting the cloud services front? Read Amazon Cuts Cloud Prices Again. ]

Founded in 2011, the 31-employee firm launched infrastructure services in January 2012 in New York and San Francisco and added an Amsterdam location in April this year. Despite its startup status, it boasts some impressive experience: co-founder Jeff Carr, who came up with the SSD-laden server approach, is the architect who designed the GoGrid Cloud, according to Mitch Wainer, VP of marketing.

By adding four 480-GB solid state memory sticks to a host server, DigitalOcean can guarantee quick interactions between CPU and storage as its customers make use of SSDs in place of revolving disks. Its most popular virtual server has a single virtual CPU, 1 GB of memory and 30 GB of SSD storage, priced at $.015 an hour. A virtual CPU or "core" in its server lineup is equivalent to a physical 2-GHz Xeon core.

The closest equivalent, CPU-wise, is a virtual CPU in an Amazon "medium" virtual server, which amounts to two Intel Xeon 1-GHz cores. (Amazon's medium server also includes 3.75 GB of memory and 410 GB of storage for $.12 an hour.)

If you're using a DigitalOcean host server and other demands on it are light, you get all the CPU available rather than being restricted to a certain percentage defined by the virtual CPU in your server selection, Wainer explained in an interview.

DigitalOcean also uses KVM, open source code supported by Red Hat, as its default hypervisor. Some benchmarks comparing it to VMware and Microsoft listed it as the fastest. KVM is embedded in the Linux kernel and uses the kernel's scheduler and memory manager rather than handing off those tasks to duplicate functions in the hypervisor software outside the operating system.

Wainer said DigitalOcean has attempted to keep its customers' access to cloud services fast and simple. "We can deploy servers in less than 55 seconds and we destroy fast [when it's time for a virtual server's life to end]," he said.

Wainer attributes DigitalOcean's rapid growth to its developer orientation. It's attracting developers at technology startups in New York and San Francisco, both centers of tech activity, and its content is oriented toward Ruby developers. Jeff Carr's Linux expertise -- he once produced the Linux PPC distribution -- helps in such content creation. The DigitalOcean community website offers step-by-step explanations of how to launch Nagios plug-ins (open source system management) on CentOS or Ubuntu, and how to use Memcached cache management with Ruby on Rails. "That's been a huge driver for us," said Wainer.

DigitalOcean's website gets nearly a million visitors a month, many of whom are developers seeking such information. The firm has done little marketing, but it follows up with most site visitors. One of its plans offers developers a virtual server for $5 a month.

The company bills customers either by the hour or monthly. Its lowest-priced virtual server is .7 cent per hour. It's more lightly equipped but roughly equivalent to an Amazon medium server (3 cents per hour, versus AWS' 12 cents per hour).

DigitalOcean's combination of SSD speed and low price make it stand out in Netcraft's survey. In the six months from December through June, Amazon added 31,321 servers; Alibaba added 10,699; Hetzner added 9,016; and DigitalOcean added 6,996.

Netcraft also tracked websites that moved to DigitalOcean from better-known competitors. 1,475 moved from Rackspace; 1,028 from Linode (Shore Network Tech), the IaaS provider included in van Woensel's benchmark; 626 from Amazon Web Services and 263 from SoftLayer (which was recently acquired by IBM).

DigitalOcean hosts Newsblur, a news aggregation site that supplies a reader for personalized real-time RSS feeds. Newsblur has enjoyed increased popularity since Google discontinued its reader on July 1. It also hosts the popular Ruby on Rails document site RubyonRails.org and Ryan Bates' popular Ruby webcast site Railscasts.com.

"We saw a need because there wasn't a cloud provider with a simple interface for launching a Rails application," Wainer explained. Users who try to do this on Amazon face a multistep process, which DigitalOcean has simplified. "We felt their pain," he added.

So far, DigitalOcean is a Linux workload-only cloud. It has delayed plans to implement Windows hosting as well, citing a need to master Windows security and licensing complexities.