[LMB] Programming, was: Re: OT: Afterlife

Matija Grabnar lmb at matija.com
Mon Nov 2 18:19:22 GMT 2020


On 11/2/20 1:45 PM, WalterStuartBushell wrote:

>   Apparently speeding up processors is cheaper than speeding up RAM.

You claim that you received TWO "nanoseconds" from Admiral Hopper, but 
you still haven't learned the lesson they were intended to teach.

A "nanosecond" admiral Hopper handed out was about 30 cm of wire, the 
distance light travels in vacuum, in one nanosecond.

Electricity in conductor travels slower than that. With the CPU 
frequencies of 3-4 GHz, one cycle is one third to one quarter of a 
second, so the signals can travel AT MOST 8-10 centimeters in that time 
(and probably noticeably less). It's not about making memory faster 
(well, sure it is, a bit, but...), it's physically about how far signals 
have to travel to get to memory and back.



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