1. 各种策略行为和优缺点 Read Through:CPU Read data Through(not Allocate) Cache to Main Memory. Read Allocate:CPU Read data from Main Memory and Allocate it in cache Write Through:CPU Write data Through Cache to Main Memory。 Write Back:CPU Write data Back to Cache. Write Allocate: CPU Wr...
我们应该知道程序是运行在 RAM之中,RAM 就是我们常说的DDR(例如 DDR3、DDR4等)。我们称之为main memory(主存)当我们需要运行一个进程的时候,首先会从Flash设备(例如,eMMC、UFS等)中将可执行程序load到main memory中,然后开始执行。在CPU内部存在一堆的通用寄存器(register)。如果CPU需要将一个变量(假设地址是A)...
1. Compare and contrast cache and main memory (RAM) accor ding to the followingaspects 2. The table below shows the main issues in cache management. Fill the table a short description and examples of strategies'polices used for each issue. 3...
比如从这种图中可以看到, 即使是l2 cache : main memory 也差不多是 1:10. 也就是说如果对于某一次访问 l2 cache 时间是 10ns, 然后内存访问的时间是100ns, 在没有优化前总的访问时间是 10 + 100 = 110ns, 在优化后访问的时间是 10/2 + 100 = 105 ns. 看起来对于延迟其实没有多大的提升. 只有5%...
数据在主存和缓存之间以固定大小的”块(block)”为单位传递,也就是每次从main memory读取的最小数据的单元。每个块的大小可能是4,8,16 Bytes或其他值,不同的CPU不尽相同,目前的x86 CPU cache line基本都是64 bytes。通常,人们更习惯称之为cache行,或者cache line。根据前一篇文章的描述,每个cache line除了包含...
A computer system and method are taught utilizing main memory and cache memory addressed in a novel manner to increase speed of operation of the computer system while minimizing the number of address pins required to fully address cache memory and main memory. A CPU address bus is shared between...
MEMORY SYSTEMS A cache memory system is described that reduces cache interference during direct memory access block write operations to main memory. A control memory 36 within cache contains in a single location validity bits for each word in a memory block. In response to the first word ...
Memory is split into a vast number of small sections known as cells. Each place or cell has a specific address that ranges from 0 to memory size – 1. There are three types of memory: Cache Memory, Primary Memory/Main Memory, and Secondary Memory....
12.1 The Memory Hierarchy and Cache Memory 12.1.1 Caches and Memory Management Units 12.2 Cache Architecture 12.2.1 Basic Architecture of a Cache Memory 12.2.2 Basic Operation of a Cache Controller 12.2.3 The Relationship between Cache and Main Memory 12.2.4 Set Associativity 12.2.5 Write ...
12、Inclusive and exclusive caches 先讨论一个简单的内存读取,单核的. 如LDR X0, [X1], 假设X1指向main memory,且是cacheable. (1)、Core先去L1 cache读取,hit了,直接返回数据给Core (2)、Core先去L1 cache读取,miss了,然后会查询L2 cache,hit了,L2的cache数据会返回Core,还会导致这个cache line替换到L1...