On Tue, Jan 12, 1999 at 02:34:04PM +0000, Alan Cox wrote:
> > Implementing swapping would be hard on XT class computer since it requires
> > virtual memory services. However shared libraries can be implemented
>
> Actually swapping is trivial if you keep the 64K+64K limit. You write the
> entire program out to disk (swap not page). When you need to run it again
> you load it back in, edit its CS:DS:ES:SS and continue. The bcc output code
> as with Minix never saves or changes segment registers
Okey :) But I thought about REAL swapping (page based) because this kind
of swapping require to swap out the WHOLE program. On heavy memory load
this would be terrible (swapping in/out a whole program almost on any
context switching ?)
There is a "middle-way" solution but it's silly as well and it requires
286. (I might have posted it too the list some months ago I don't remember
exactly). Set segment size to for example 1. If the code (or data)
try to read/write offset greater then this we got an exception.
But I don't know how we can get the offset (because we must to load
from hdd data between the setted segment size and the offset casued the
exception). Maybe we must write an instruction decoder or seomthing ?!
It looks bad. But it can be considered ...
- Gabor (LGB)
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"The truth is out there" "We're l{ea,i}ving together" "The future is dark."
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