[yan]

For a way more detailed look at memory architectures and implementation, check out Ulrich Drepper's classic paper "What Every Programmer Should Know About Memory"[1]

[1] http://www.akkadia.org/drepper/cpumemory.pdf

[demallien]

Or on a more light-hearted note: http://folklore.org/StoryView.py?project=Macintosh&story=Sou...

Which just goes to show, hitting memory is a Bad Thing(tm) even when you're running on a slow(from today's perspective) processor like a 68000.

[raverbashing]

Very impressive

Doing 22kHz generation on a Macintosh is very close to the limit

[derleth]

It wasn't always thus: On the 6502, which the early Apple II machines were built around, it was possible to access RAM at only a one- or two-cycle penalty compared to doing everything in registers and immediate values. This was only the case if you used zero-page memory without indexing, however, so you couldn't have a lot of stuff in RAM without incurring more speed penalties.

http://www.6502.org/tutorials/6502opcodes.html

(Zero-page memory on the 6502 was the memory accessed via addresses with a high byte of 0x00. Since 6502 had sixteen-bit RAM addressing, this meant each page was 256 bytes large, so the zero-page was almost as good as having 256 single-byte registers.)

[bloodorange]

This, ladies and gentlemen, is a particularly detailed and good read. Please do give it a glance if you haven't already.

[solarexplorer]

If you want to buy good book on the topic: "Memory Systems: Cache, DRAM, Disk" by Bruce Jacob, Spencer Ng, David Wang

[yan]

A few days late, but thanks