On Thu, 5 Mar 2020 21:28:09 -0500 James Knott <james.knott@jknott.net> wrote:
On 2020-03-05 09:24 PM, James Knott wrote:
On 2020-03-05 04:48 PM, Anton Aylward wrote:
Nonsense! "Virtual memory means virtual performance" was the idiom from the 1960s when IBM and others fist implemented virtual memory with little understanding for the algorithms! Back the a IBM/370 with 256K of memory was typical. Linux is more sophisticated and can always use the memory, somehow.
My first experience with virtual memory was with DEC VAX 11/780 systems. Prior to that, we had overlays, where portions of code were swapped into memory. This was used with head per track disks.
There's a pretty good summary of the history of virtual memory and thrashing at http://denninginstitute.com/pjd/PUBS/bvm.pdf
Forgot to mention, between overlays and virtual memory, we had systems with paged memory, which had more memory than could be addressed by the CPU. Blocks of memory were switched into the CPU address range as needed.
If you're thinking of the same thing as me, we usually called that 'banked' memory. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org