22 Apr
2024
22 Apr
'24
1:47 p.m.
On Apr 22, 2024, at 4:21 PM, Mike Katz via cctalk
<cctalk(a)classiccmp.org> wrote:
Once CPUs became faster than memory the faster the memory the faster the CPU could run.
That is where CACHE came in. Expensive small high speed ram chips would be able to feed
the CPU faster except in case of a cache miss and then the cache had to reload from slow
memory. That is why multiple cache buffers were implemented so one could be filling
(predicatively) while another buffer was being used.
An early cache, though not called that, is the track buffer in the ARMAC, a 1955 or so
research computer built at CWI (then called MC) in Amsterdam. Its main memory was a drum,
like its predecessors, but it would keep the most recently accessed track in memory
(core?) for fast access. That was handled in hardware if I remember right, so it's
exactly like a one-entry cache with a line size of whatever the track length is (32
words?).
paul