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The thing I find interesting about OS/400 (or whatever it's name is this month) is the single-level store. When your program needs access to the contents of a
by chiph 13y ago
The thing I find interesting about OS/400 (or whatever it's name is this month) is the single-level store. When your program needs access to the contents of a file, it's just a memory offset. The OS relies on the swapping mechanism to bring those pages into available memory. Which, when you have flat 64 (one could argue 65) bit addressing … why not?
- pjmlp 13y agoThat is why I always call it by the original name. :) Yep that is also a nice feature.
- angersock 13y agoWait wait wait...so it effectively memory maps all the things? Mainframe environments are weird.
- pjmlp 13y agoAnd OS/400 files are libraries that you need to open, as another example of strangeness. Or the OS/360 which uses virtualization for all OSs, like Hyper V does on Windows. The first OS to boot from the hypervisor has master rights, but all OSs are virtualized.
- fulafel 13y ago> Or the OS/360 which uses virtualization for all OSs, like Hyper V does on Windows No, the hypervisor was called VM. According to WP it most frequently ran CMS guests, which was a light weight single-app OS. But could also run OS/360 guests (which predated VM).
- derleth 13y agoAS/400 isn't mainframe. It's midrange; smaller than a mainframe, and not as flexible.
- rodgerd 13y ago"Everything's a file!" "No, everything's memory!"