Stability doubts as Unisys lowers datacentre costs using Windows.
Users will have to wait years before they can replace Unix with Windows 2003, despite the introduction of a new server that beats rival Unix operating systems on both price and performance.
Last week Unisys introduced a revamped version of its high-end ES7000 server family in a bid to lower the entry costs for building Windows 2003 installations with Unix levels of scalability.
While the hardware supports dynamic partitioning - a Unix-like function to reallocate computer workload on the fly - some industry commentators have argued that Windows 2003 cannot use this functionality.
Microsoft has claimed Windows 2003 is capable of competing with the largest Unix systems. However, Andy Butler, an analyst with Gartner, said, "Windows 2003 is not ready to replace Unix."
While he acknowledged that Windows 2003 could be deployed in a lot of situations where Unix would traditionally be used, Butler said, "Windows 2003 does not start to catch up with Unix in terms of availability and manageability." For example, he said Windows 2003 failover clustering was "more junior than Unix".
Butler said that while the new Unisys ES7000/500 server had been engineered so that users can allocate any system resource in real time, Windows 2003 was not smart enough to support this.
He said the 32-processor ES7000 was still limited by the confines of the Windows 2003 operating system. According to Butler, HP-UX and Solaris systems have made more progress than Windows 2003 in terms of being able to reconfigure servers without rebooting.
"There is less need to close or reboot parts of a Unix system to add memory or additional disc capacity," he said.
Rakesh Kumar, an analyst with Meta Group, said, "The lack of dynamic partitioning and virtualisation technology in Windows 2003 is a significant handicap." He said Windows 2003 had no chance of encroaching on the Unix datacentre without these key features.
"Users require dynamic partitioning and virtualisation for workload management," Kumar said. These features are at least two to three years away, as Microsoft develops the next "Longhorn" release of Windows.
Michael Hjalsted, marketing director at Unisys, admitted that while the Unisys ES7000/500 server could support dynamic partitioning and allowed memory and discs to be installed in real time, Windows 2003 does not support these features.
Mark Tennant, UK product manager for Windows 2003 Server, said Microsoft would be releasing a preview of its Virtual Server technology on 15 April. This software is intended to address dynamic partitioning in future Windows releases.
How Unix and Windows measure up
Unlike Windows 2003, memory and disc capacity on Unix systems can be extended without rebooting
Failover clustering on Windows is not as sophisticated as Unix failover
True dynamic partitioning is not expected in Windows for the next two to three years
Windows 2003 cannot support all the partitioning functionality within the Unisys ES7000
Unisys ES7000/500 running Windows 2003/SQL Server 2003 gave a TPM/C benchmark of 183,381 transactions per minute at $5.56 per transaction.