Re: "super-expensive mainframes"
I remember when an IBM Z13 Mainframe started at about $1.5 Million US dollars when you counted in the support contract which gets renewed every year at about $50,000 to $75,000 per year (at least for us!)
Just recently, an old used IBM Z-13 mainframe was put on sale for about $100,000 US ... I'm kinda tempted to put it in my basement but POWERING the thing is a pain! Even though the Z-13 is old (2015), you can put 10 Terabytes of RAM into it and can STILL run way over 2019 era 100,000+ full-graphic website processes on it. We NEVER got it that high because our incoming connections in the mid 2010's maxed out at 20 Gigabits or so.
i've always liked the big iron for concurrent workloads ... those ibms are GREAT for that.
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