This simple principle is particularly applicable to memories built from the same technology for two reasons:
In high-speed machines,
signal propagation
is a major cause of delay;
In most technologies we can obtain smaller memories that are faster than
larger memories. This is primarily because the designer can use
more power per memory cell
in a smaller design;
The important exception to the smaller_is_faster rule arises from differences in power consumption. Designs with higher power consumption will be faster and also usually larger. Thus, the smaller-is-faster rule applies only when power considerations are taken into account.