Contents
What does a cache block contain?
Each cache block contains 16 bytes. Calculate the number of bits in the TAG, SET, and OFFSET fields of a main memory address.
What are the components of cache?
12.2. A simple cache memory is shown on the right side of Figure 12.4. It has three main parts: a directory store, a data section, and status information. All three parts of the cache memory are present for each cache line. The cache must know where the information stored in a cache line originates from in main memory.
What are the five main elements for cache design?
Five elements in cache design: Cache Size. Block Size. Mapping Function. Replacement Algorithm.
What is cache associativity?
A fully associative cache permits data to be stored in any cache block, instead of forcing each memory address into one particular block. — When data is fetched from memory, it can be placed in any unused block of the cache.
How many blocks are there in a cache?
A simple cache design. Caches are divided into blocks, which may be of various sizes. —The number of blocks in a cache is usually a power of 2. —For now we’ll say that each block contains one byte. This won’t take advantage of spatial locality, but we’ll do that next time. Here is an example cache with eight blocks, each holding one byte.
How to calculate the number of bits in the cache field?
Calculate the number of bits in the TAG, SET, and OFFSET fields of a main memory address. Answer Since there are 16 bytes in a cache block, the OFFSET field must contain 4 bits (24= 16). To determine the number of bits in the SET field, we need to determine the number of sets.
Which is the effective address of the cache row?
The block offset specifies the desired data within the stored data block within the cache row. Typically the effective address is in bytes, so the block offset length is ⌈ log 2 ( b ) ⌉ {displaystyle lceil log _{2}(b)rceil } bits, where b is the number of bytes per data block.
Which is part of the cache contains the actual data?
The data block (cache line) contains the actual data fetched from the main memory. The tag contains (part of) the address of the actual data fetched from the main memory. The flag bits are discussed below. The “size” of the cache is the amount of main memory data it can hold.