1.3-一、Memory System Desiderata

1.Memory System Desiderata
The Memory system has three desiderata.
(1)Size:infinitely large,no constraints on program of data set size.
(2)Speed:infinitely fast,latency equal to the fastest memory technolgy available.
(3)Cost:per bit cost should approach the lowest-cost technology available.
Clearly,these specifications cannot all be achieved as they are mutually exclusive.
However, with the semiconductor and magnetic memory technology of today,these
specifications are closely approximated.

1.Memory System Desiderata
The Memory system has three desiderata.
內存系統設計內存系統有三個設計。
(1)Size:infinitely large,no constraints on program of data set size.
（1）大小：無限大，對數據集大小的程序沒有限制。
(2)Speed:infinitely fast,latency equal to the fastest memory technolgy available.
（2）速度：無限快，延遲等於最快的可用內存技術。
(3)Cost:per bit cost should approach the lowest-cost technology available.
（3）成本：每比特成本應接近可用的最低成本技術。
Clearly,these specifications cannot all be achieved as they are mutually exclusive.
顯然，這些規格不可能所有實現，由於它們是相互排斥的。
However, with the semiconductor and magnetic memory technology of today,these specifications are closely approximated.
然而，隨着當今半導體和磁存儲技術的發展，這些規範獲得了密切的近似。

1.3 存儲器
1.存儲系統的需求
存儲系統有一下3項需求。
（1） 容量：無限大，對程序和數據集大小沒有任何約束。
（2） 速度：無限快，等待時間在現有存儲器技術下是最短的。
（3） 價格：每位的價格在可以使用的技術中應最低。
很明顯，因爲這3個需求相互制約，因此很難所有知足。不過隨着半導體和磁存儲技術的發展，這些需求幾近獲得知足。