On Wed, Jul 11, 2018 at 11:29:51PM +0200, R.S. wrote: > W dniu 2018-07-11 o 20:07, Tom Marchant pisze: > >On Wed, 11 Jul 2018 18:06:59 +0200, Tomasz Rola wrote: > > > > >BTW, would it count as a mainframe if I ran one inside emulator > > >on PC? > >Sure, if you can emulate 170 processors, 32 TB of main memory, 320 > >FICON channels, and robust error handling.
170 cpus. 32TB of ram? Uh, sure. Just not very fast - I only have 4 real cores and 12GB of ram, the rest would have to be swapped on 4TB harddrives. But I guess not every mainframe is so well packed to the roof. BTW, what I mean by mainframe is a bit more extended and covers not only modern incarnations of it. But, ok, I can easily agree that emulated modern mainframe is not really mainframe. And thus it does not count as such. > >There is much more to a mainframe than the instruction set. > > > Take care, current PC servers can have more memory than mainframe. > It have been true for at least 10-15 years. Current PC do support > 32Gbps FC and 40Gbps or 100Gbps LAN NIC. How many? Enough. I can't > tell current processor limits, but it is at least half of mainframe. > Last, but not least: such PC server beast cost still much less than > mainframe. Who cares? Managers. I would tell those managers that PC comes with their own baggage of, well, manure. I had once a motherboard whose condensers went poof (sometimes they go poof -> open up, sometimes they go bloop -> leak). I guess condensers used to build mainframes go neither poof nor bloop. That is a huge plus, because one does not have to get inside in order to solder in new condensers. Also, as of recently, there is ongoing discovery of nasty design bugs inside Pentium-compatibles - rowhammer, meltdown, spectre, recent fpu related one which has no name yet (I guess) and possibly some more coming, if I am to believe rumors on the net. The lack of such "features" on a mainframe may be a big selling point, if someone could actually verify that indeed there is no such features on big iron. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home ** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:[email protected] ** ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
