Four versions of Linux have outstripped UnixWare in D.H. Brown Associates comparative analysis of operating systems, the first time Linux has surpassed any version of Unix.
"The gap between Linux and Unix systems has certainly closed at a rapid pace," said Tony Iams, senior analyst and author of the study, 2001 Linux Function Review. At the same time, he said, "even the strongest Linux products continue to lag behind the leading RISC [reduced instruction set computing]-based Unix systems [such as Hewlett-Packards HP-UX, IBMs AIX or Sun Microsystems Solaris] in terms of functional capabilities."
According to the report, the strongest Linux products, in declining order, are: SuSE Linux 7.2, a version particularly popular in Europe; Red Hat Linux 7.1; Caldera Internationals OpenLinux 3.1; and Turbolinux 6.5. Three of the distributions are based on the latest Linux kernel, version 2.4, which helped propel them beyond UnixWare. Turbolinux is still based on the 2.2 kernel.
UnixWare is the version of Unix formerly sold by Novell, along with its NetWare local area network OS. It was in turn sold to the Santa Cruz Operation, which last year sold it to Caldera.
SuSE Linux 7.2 held the lead among the studied distributions, due to its strengths in reliability, availability and serviceability (RAS). It possesses "superior workload management capabilities, and support for both mainframe partitions in its [IBM mainframe] implementation and emerging resource management tools," the report said.
It shares several strengths in storage reliability functions with Turbolinux, including a journaling file system and Logical Volume Manager. The journaling file system reduces data loss in a system crash by creating a journal of events that preceded the crash. The Logical Volume Manager enables online file system backup. Caldera includes a journaling file system, but no online backup capabilities. Red Hat does not include a journaling file system, the report said.
"Commercial Unix systems support far more advanced RAS features than any current Linux system," Iams noted.
Red Hat scored the highest among the distributions for scalability features, and it offers good clustering support. SuSE "follows close behind, slightly hampered by a lack of published benchmark results and a lack of support for key third-party load balancing software," the report said. Caldera does not yet support 64-bit processor architecture, such as Intels Itanium or Compaq Computers Alpha, the report said.
In the 1999 edition of the OS study, D.H. Brown analysts concluded that Linux was primarily a system for low-end Web servers, file and print servers, appliance servers and clustering for high-end technical computing. This years study leads to the conclusion that Linux "is quite capable of serving as a general-purpose operating system for a broad range of departmental and workgroup applications," making it a direct competitor with low-end Unix and Windows 2000 Server, Iams said.
"People ask me, When is NT/Windows 2000 going to wipe out Linux and Unix? Its not going to happen," he said, due to the ongoing strength of Linux and Unix, and because Windows appeals to a different audience.
"Unix people like choice everywhere," Iams said. "They want a small, relatively simple kernel, and best-of-breed additions around the kernel" - a demand that has helped the growth of Linux, he said.
Windows users prefer an easier-to-administer system with a strong graphical management interface, he added.