Zynga's hybrid cloud strategy helps it cope with the risk of unpredictable demand for new online games.
The Private Cloud
Zynga's Z Cloud is designed to function much like EC2 in the way it provisions, tracks, and manages both physical and virtual machines. With 250 million active users a month, Zynga IT must rely on automation to carry out many routine tasks in the combined infrastructure. Virtualization is indispensable. "We see virtualization as a very flexible mechanism for changing the environment on the fly," Leinwand says.
Zynga's team has built the Z Cloud management software layer over several years of successful game operations. It uses open source code for network management and systems management components, but they've been heavily customized by Zynga IT. (Leinwand won't name the open source parts, saying he doesn't want hackers to know too much about the roots of his systems.) With this homegrown management system, he and his staff can do something most companies can't imagine: "On a given day, if we need to, we can deploy a thousand servers," he says. That's a thousand physical, not virtual, machines. Zynga staffers stand those up inside the company's leased data center space.
Zynga can do so in part because the servers it deploys are highly standardized, coming in just two sizes. The Z Cloud uses the most recent Westmere generation of Intel Xeon processors, either two- or four-socket servers with 24 to 96 GB of RAM and 140 to 600 GB of disk. Zynga has tried to minimize the number of hardware configurations it has, Leinwand says.
That standardization eliminates possible conflicts in server chip architectures as Zynga applies its virtualization management system, largely an in-house customization of available open source code. Moving virtual machines around to best exploit available servers is a surer thing when moving to a matching chip architecture. Minute differences in the x86 instruction set between successive iterations of the same chip can introduce glitches when the shift occurs between dissimilar chips.
That insistence on uniformity is in marked contrast to the typical company's data center, which is stocked over 10 or 20 years with best-of-breed systems for various parts of the business. The result is a wide variety of hardware and software architectures that make for a complex infrastructure. Large database systems might run on big Unix servers, Web servers on small Linux-based x86 boxes, departmental systems on various versions of Windows, and maybe even a 30-year-old business application still running on a DEC VAX or HP MPE machine. That typical data center requires a high-touch server administrator staff -- lots of manual interventions -- to keep it running.
Zynga, as a newcomer, has kept its infrastructure relentlessly simple. "We don't have one of everything," Leinwand says.