from Hacker News

Four Facts Millennials Need to Know About the Mainframe (2014)

by Lukman on 4/8/19, 3:54 AM with 4 comments

• by DrScump on 4/8/19, 4:34 AM

  "Since mainframe computers are almost always running at 100% utilization..."

  That's essentially impossible, as either CPU or I/O will bottleneck first and be the limiting factor.

  As an operator, I used to make note of how different jobs used resources so I could keep overall utilization as high as possible, blending I/O bound jobs with CPU heavy jobs. (This was graveyard shift, where real-time users were few)

  There was a great Boole and Babbage product called Resolve that allowed the operator (or a TSO user) to dynamically change job priorities as desired.

• by DrScump on 4/8/19, 4:39 AM

  "Mainframes provide the lowest cost of ownership. First the efficient mainframe power and cooling requirements are much cheaper than equivalent distributed UNIX or Windows platforms."

  This makes no sense to me at all. For decades, you could have far lower $/MIPS using minis and micros. Simply needing the whole raised-floor, halon-protected environment and custom peripherals (and specialized personnel) seems cost-prohibitive if not needed from a legacy standpoint.

• by lainga on 4/8/19, 3:58 AM

  Dave Beulke's boss walks into his office, throwing a stack of market research papers on his desk.

  "What's th-?", Dave starts, but is cut off.

  "MILLENNIALS MILLENNIALS MILLENNIALS", his boss replies, and is gone without another word.

  http://enterprisesystemsmedia.com/article/three-more-reasons...