6 ms·
Mainframes are fast because each given "run time" (aka VM) has a fixed set of resources (aka Capabilities). Unlike the PC world, the default access is NO to any
by mikewarot 4y ago
Mainframes are fast because each given "run time" (aka VM) has a fixed set of resources (aka Capabilities). Unlike the PC world, the default access is NO to any other files, etc.
We in the PC world keep reinventing our terms, the Mainframe folks just keep using the ones settled on decades ago.
You can run a VAX 11/780 in an Emulator, the same is true of many older Mainframes.
There's nothing magic about them, they're just optimized for throughput, in a very specific context.
- arethuza 4y agoI didn't think a VAX 11/780 was considered a mainframe - rather a minicomputer?
- lproven 4y agoAgreed. The VAX 9000 range tried to become mainframes, and the effort to make them bankrupted DEC. But there are non-IBM mainframes. They do run under emulation on x86, but they are still real. Unisys Clearpath, for instance.
- arethuza 4y agoThe CS course I did in the 1980s had us use a Burroughs mainframe for the first year (complete with MCP) - I think this was a cunning ploy to make us really appreciate Unix when we got to use for the remaining three years....
- lproven 4y agoJust curious: in what ways? I started out on VAXen before I learned DOS or Xenix, and frankly, I preferred it. File versioning was wonderful and with that as a basis, we'd never have needed the vile baroque mess that is Git.