What is Memory Latency?

Question

I can see RAM states memory latency of something like 4-4-4-12. What is that?
Is a smaller number, eg, 3-4-3-9, indicates better?
Thz

Answer 1

延迟的描述 4-4-4-12 這四個數字義思是"CAS", "RAS-to-CAS", RAS Precharge, 和Act-to-Precharge

延迟的描述可以用四个用“-”分开的阿拉伯数字表示，比如2-2-2-5。第一个数字代表CAS(Column Address Strobe)延迟时间，这个数字非常重要。接下来是RAS(Row Address Strobe)-to-CAS延迟，RAS Precharge延迟和Act-to-Precharge延迟。

CAS的延迟时间
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Is a smaller number, eg, 3-4-3-9, indicates better?
Yes