Editing UNIX System V (section)

=== System V and the Unix market ===
By 2001, several major Unix variants such as SCO UnixWare, Compaq [[Tru64 UNIX]], and SGI IRIX were all in decline.<ref name="2001_vital_signs"/> The three major Unix versions doing well in the market were IBM AIX, Hewlett-Packard's HP-UX, and Sun's Solaris.<ref name="2001_vital_signs"/>

In 2006, when SGI declared bankruptcy, analysts questioned whether Linux would replace proprietary Unix altogether. In a 2006 article written for ''[[Computerworld]]'' by Mark Hall, the economics of Linux were cited as a major factor driving the migration from Unix to Linux:<ref name="2006_end_of_unix">{{citation|url=http://www.computerworld.com/article/2555262/operating-systems/the-end-of-unix-.html|title=The End of Unix?|author=Mark Hall|date=15 May 2006|access-date=5 June 2015}}</ref>

{{quote|Linux's success in high-end, [[scientific computing|scientific]] and [[high-performance technical computing|technical computing]], like Unix's before it, preceded its success in your [[data center]]. Once Linux proved itself by executing the most complex calculations possible, IT managers quickly grasped that it could easily [[web server|serve Web pages]] and run [[payroll]]. Naturally, it helps to be lucky: Free, downloadable Linux's star began to rise during one of the longest downturns in IT history. With companies doing more with less, one thing they could dump was Unix.}}

The article also cites trends in high-performance computing applications as evidence of a dramatic shift from Unix to Linux:<ref name="2006_end_of_unix"/>

{{quote|A look at the [[TOP500|Top500]] list of [[supercomputer]]s tells the tale best. In 1998, Unix machines from Sun and SGI combined for 46% of the 500 fastest computers in the world. Linux accounted for one (0.2%). In 2005, Sun had 0.8%&nbsp;— or four systems&nbsp;— and SGI had 3.6%, while 72% of the Top500 ran Linux.}}

In a November 2015 survey of the top 500 supercomputers, Unix was used by only 1.2% (all running IBM AIX), while Linux was used by 98.8%; the same survey in November 2017 reports 100% of them using Linux.<ref name="top500_stats">{{cite web|url=http://www.top500.org/statistics/list/|title=TOP500 Supercomputer Sites - List Statistics|access-date=28 January 2016}}</ref>

System V derivatives continued to be deployed on some proprietary server platforms. The principal variants of System V that remain in commercial use are AIX (IBM), Solaris (Oracle), and HP-UX (HP). According to a study done by [[International Data Corporation|IDC]], in 2012 the worldwide Unix market was divided between IBM (56%), Oracle (19.2%), and HP (18.6%). No other commercial Unix vendor had more than 2% of the market.{{r|lastdays}} Industry analysts generally characterize proprietary Unix as having entered a period of slow but permanent decline.<ref>{{cite web|url=http://www.computerworld.com/article/2486806/linux/as-unix-fades-away-from-data-centers--it-s-unclear-what-s-next.html|title=As Unix fades away from data centers, it's unclear what's next|author=Patrick Thibodeau|date=12 December 2013|access-date=6 June 2015|archive-url=https://web.archive.org/web/20150520013205/http://www.computerworld.com/article/2486806/linux/as-unix-fades-away-from-data-centers--it-s-unclear-what-s-next.html|archive-date=2015-05-20}}</ref>