eWEEK 30: Unix Proves Staying Power as Enterprise Computing Platform
Microsoft specifically targeted Xenix for deployment on the IBM PC and XT machines running Intel x86 chips. While Microsoft today is best known for its Windows operating system, Xenix was released five years before the first Windows 1.0 release in 1985. The Santa Cruz Organization (SCO) began to use Xenix in 1983 as part of its own flavor of Unix that it sold for the IBM PC. Microsoft exited the Xenix business in 1987, selling 75 percent of its Unix assets to SCO. Xenix wasn't the only flavor of Unix to run on x86. Sun first ported Unix to the x86 platform in 2003, and Oracle continues to support Unix on x86 as well as SPARC in 2013. By the mid-1990s, Befi said it became clear that Unix would play a bigger role in the enterprise, which is something that remains true to this day. Befi recounted that during the mid-1990s there was an office pool on his whiteboard at IBM about when the last mainframe in the world would be unplugged. The prevailing notion at the time was that all the mainframe workloads would migrate to Unix.Long-Term Compatibility In 1992, a tectonic shift occurred in the Unix space when Sun defected from its BSD roots. That year, Sun launched Solaris, which was the first Sun Unix operating system to be based on AT&T's Unix System V. Oracle's Flierl noted that there was a lot of market upheaval when Sun shifted from Sun OS to Solaris. Flierl now leads Solaris development for Oracle, which acquired Sun in 2010 for $7.4 billion. The 1992 Sun Unix upheaval wasn't just about a name change; the move to the AT&T Unix base from BSD also brought with it software compatibility and porting issues. The lesson of that era has echoed through the rest of Unix history, and binary compatibility is now a core tenet for Solaris, as well as other Unix vendors. With binary compatibility, software vendors can rest assured that software will survive and be supported on the operating system for years at a time instead of just from release to release. The ability to have binary compatibility in Unix has also been impacted by the underlying hardware platforms used by vendors. HP-UX of the 1980s was tied to HP's PA-RISC silicon architecture. By the mid-1990s, HP embraced Intel's Itanium architecture instead as the basis for its Unix systems. HP-UX has been at Version 11 since 1997, in part as a testament to the fact that all releases since then have compatibility as a core feature. HP stresses that fact by keeping the same version number in place. HP's Bresniker noted that each update to HP-UX Version 11 and in particular the 11i updates have all been long-lived releases, in contrast to the early HP-UX releases of the 1980s when there were frequent major updates.
"The reality is that though things shift over time, not all workloads moved off the mainframe to Unix," Befi said.