In the latest Server Tracker report from Framingham, Mass-based research firm Quarterly Server Tracker report , the annual revenue growth rate for Linux shipped on x86 commodity hardware was -4% in 2006; down from the 53% mark it set in 2003. Windows Server growth for the same period was more than 20%. Also in 2006, worldwide Linux x86 server shipments decreased from an annual growth rate of approximately 45% in 2003 to less than 10% last year. Today, Microsoft Windows comprises roughly 70% of the North American x86 market, Linux has slightly more than 20%, and Unix has less than 10%, according to IDC research.
And Q2 of this year marked the first time since IDC began tracking Linux server spending in 1998 that Windows Server revenue grew faster than Linux server revenue. Linux server revenues had a second consecutive quarter of double-digit growth at 10%, and Windows Server 2003 had 10.4%, according to the Q2 Server Tracker report.
But before Linux supporters begin to sound the doomsday alarm, one expert emphasized that the real battle has always been between Unix and Linux, not between Linux and Windows. There's also some question about whether the Server Tracker report, long a staple of the industry for gauging trends in server deployments, might ignore substantial new areas of Linux growth.
Linux instances and mainframes
Charles King, principal analyst and founder of Hayward, Calif.-based research firm Pund-IT Inc., said the new IDC numbers underscore a constant issue in Linux market development: Linux has been a greater threat to Unix and NetWare than to Windows. This is partly because of the similarities between Linux and Unix distributions, which enabled Unix system administrators to work with and adapt Linux applications for their own purposes, he said.
"As these IDC numbers seem to suggest, there is only so much Unix 'fruit' to harvest -- unless Linux apps make inroads on more business critical applications," King said. "At the same time, it seems to me that there are also greenfield opportunities for Linux in areas that IDC may not be capturing."
One such area is the mainframe space, King said. IBM Corp., for example, has declared that more than half of the new mainframe million instructions per second it sells are Linux-based, and the company is working hard to position Linux-on-System z as an ideal server consolidation solution.
IDC's own methodology reveals that x86-to-mainframe consolidations are not included in the research; only new hardware purchases are considered. On the Server Tracker Web site, the firm said, "IDC's server revenue includes components that are typically sold today as a server bundle, including frame or cabinet and all cables, processors, memory, communication boards, and OS." Therefore, a company consolidating a swath of x86 servers onto a single mainframe running thousands of Linux instances would be counted as only one unit.
So real-world examples like IBM's massive mainframe migration, announced earlier this year, are moot as far as Server Tracker is concerned. In August, IBM announced it would consolidate 3,900 Unix and x86 servers onto 30 mainframes, a move the company says will save it $250 million in energy, software and support costs.
CentOS and Ubuntu
There has also been criticism of IDC's report because it ignores "free" Linux distributions like CentOS and Ubuntu – both of which have been successfully installed in enterprise environments as replacements for Windows and Unix on legacy hardware. IDC calculates OS growth based on new hardware purchases and which OS is installed at time of purchase, so a Unix-to-CentOS migration of any size deployed on existing hardware would not be considered.
Brian Bouterse, a network administrator and systems specialist with the Friday Institute, an education technology innovator based in Raleigh, N.C., has deployed CentOS 5 in mission-critical areas of his infrastructure. Since his CentOS "zero-dollar price point" deployment was done on existing hardware, it would have been missed by IDC. In this atmosphere, many analysts, King included, believe revenue numbers aren't as central a factor in measuring Linux growth as they once were.
The failure to include Ubuntu deployments in particular could also be considered a shortcoming of the IDC report, since it seems to be an increasingly legitimate alternative for enterprise servers.
In May, for example, Dell Inc. announced the availability of pre-installed Ubuntu on its desktops and laptops, and rumors continue to circulate that the company will extend the program to encompass parts of its server line in the near future. And Gerry Carr, marketing manager for Canonical Ltd., said that talks are under way with hardware vendors other than Dell to pre-install Ubuntu on other brands of commodity servers.The head-to-head battle
Sooner rather than later, the low-hanging Unix and NetWare fruit will be picked clean. Already, Unix growth is expected to fall off by 2009, as it's unlikely that any new Unix applications will be developed solely for that OS after that year, said Gartner Inc. research vice president George Weiss at the firm's annual Gartner Open Source Summit in September.
With that dropoff, King said commercial Linux vendors like Red Hat and Novell Inc. will be forced to compete head to head with Windows – and that the new competition will be formidable.
"Microsoft has gained considerable ground with the dramatic rise in popularity of x86 servers," Pund-IT's King said, and by developing "improved applications and features. The success of Linux in such circumstances depends to a large extent on the willingness and innovative efforts of independent Linux developers. To say that competing against Microsoft's well-organized Windows Server efforts will be a serious challenge is an understatement," he said.