Linked by Sean Haas on Wed 28th Dec 2011 23:41 UTC
OSNews, Generic OSes There are two main kernel architectures for large operating systems; monolithic and micro. While these architectures are well thought out, well implemented (usually), and well understood, they have their faults. Mainly, the loading of modules and executables, management of memory, and interfacing between the kernel and software cause these architectures to be vastly complex. With this complexity comes a loss of speed and increased difficulty for the developer. There are other kernel architectures, such as the exokernel, that are vastly different from traditional architectures, but they still have performance issues caused by userland processes.
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Real mode?
by Zifre on Thu 29th Dec 2011 02:47 UTC
Zifre
Member since:
2009-10-04

Very interesting. I'm glad to see more actual OS news on OSNews.

However, this is pretty pointless if it is only in real mode. If the purpose of this architecture is to get speed and simplicity, this is ridiculously stupid. You have to jump through hoops to code for real mode, and it's going to be slower anyway. Not to mention that you can't do real IO (IIRC) and have to rely on super slow BIOS interrupts...

Reply Score: 2

RE: Real mode?
by Alfman on Thu 29th Dec 2011 03:04 in reply to "Real mode?"
Alfman Member since:
2011-01-28

Zifre,


"However, this is pretty pointless if it is only in real mode. If the purpose of this architecture is to get speed and simplicity, this is ridiculously stupid. You have to jump through hoops to code for real mode, and it's going to be slower anyway."

Yep, I cannot think of a single good reason to design an OS around real mode today. 64K segments are a major impediment for any real load - unable to represent even a single bitmap without mucking around with intra-segment hacks. Even if those are overcome, you're still limited to some 640K of base memory.

Of course you can use "flat real mode", so the 64k limit is removed. But that implies switching to protected mode and back, why not just use protected mode?



"Not to mention that you can't do real IO (IIRC) and have to rely on super slow BIOS interrupts..."


It's not necessary to use BIOS interrupts in real mode any more than it is from protected mode. The only IO problem you'd have is reaching memory mapped devices that aren't mapped within the first 1MB.

Reply Parent Score: 2