<p>Linux certainly has  established itself as a prominent server OS these days, pushing Unix  into the background. But the open source OS shares the stage with  commercial software giant Microsoft, which remains a dominant player  with Windows Server.</p>
<img src=\"/edesk/images/Windows-vs.-Linux1_.jpg\" alt=\"\" width=\"351\" height=\"145\" />
<p><strong>[ The</strong> <strong><strong><strong>InfoWorld</strong> <a href=\"http://www.infoworld.com/article/08/02/25/09TC-windows-server-2008_1.html?source=fssr\">Test Center rates Windows Server 2008</a>. | Why <a href=\"http://www.infoworld.com/article/08/06/09/Linux_beats_Windows_2008_powersaving_measures_1.html?source=fssr\">Linux is greener</a> than Windows Server. | Has <a href=\"http://www.infoworld.com/article/08/09/24/39NF-linux-killing-solaris_1.html?source=fssr\">Linux killed OpenSolaris</a>? ]</strong></strong></p>
<p>A  lot of Linux usage is in Web server applications, but it\'s become  increasingly common in mission-critical applications, Weiss notes. But  \"I don\'t have an indicator that says Linux is chewing up the market for  Windows,\" he adds.</p>
<p>Other forms of Unix  continue to fade away in what is becoming a two-OS choice for IT. \"The  key here is that really Linux and Windows are moving away from the pack  here and it\'s becoming a two-horse race,\" says Jim Zemlin, executive  director of the Linux Foundation.</p>
<p><strong>Both Linux and Windows Server see datacenter growth<br /> </strong>Regarding  migration of current workloads, 43 percent of respondents in a Gartner  survey at a Linux-oriented conference anticipated migrating mostly from  Unix to Linux, 13 percent said they would migrate mostly from Windows to  Linux, and only 4 percent said they would switch off Linux to go to  Windows. Twenty-one percent had no plans to migrate workloads.</p>
<p>Gartner  expects IT organizations to shift their focus to more-complex Linux  deployments and continue a trend of migration from Unix. Gartner found  that 52 percent of respondents anticipate that the total workload of  their Linux server environment will increase moderately in 2008; another  25 percent said there would be a substantial increase. Only 5 percent  anticipated moderate decrease, while 4 percent expected a substantial  decrease in Linux workloads for this year. Respondents were three times  more likely to migrate workloads from Unix to Linux than from Windows to  Linux.</p>
<p>Although Linux growth is strong, so  is that of Windows Server, according to Gartner\'s research. Linux was  ranked by 39 percent of respondents as the OS expected to have the most  growth in their datacenters during the next five years. Windows was a  close second, ranked as the OS with the most growth potential by 35  percent of respondents at the Linux-oriented conference.</p>
<p>Based  on Gartner\'s annual estimates for worldwide server shipment revenues,  both Windows Server and Linux will increase. Windows Server sales will  move from about $20 billion last year to roughly $22 billion in 2012;  Linux will grow from about $9 billion last year to $12 billion in three  years. But because Linux is often provided at no cost (with vendors  making revenues from support contracts and other services), those  numbers may not be comparable.</p>