How many sets are in a two way associative cache?

32 sets
Since each cache block is of size 4 bytes and is 2-way set-associative, the total number of sets in the cache is 256/(4 * 2), which equals 32 sets.

What is 2 way set associative cache?

Each set contains two ways or degrees of associativity. Each way consists of a data block and the valid and tag bits. The cache reads blocks from both ways in the selected set and checks the tags and valid bits for a hit. Most commercial systems use set associative caches.

How many blocks are in each set of a 4 way set associative cache?

four blocks
We are given that this is a 4-way set-associative cache, hence each set has four blocks. It holds: #Blocks = Capacity / BlockSize = 2^20 / 2^6 = 2^14.

How many sets are in a full associative cache?

Memory Systems A memory address can map to a block in any of these ways. A fully associative cache is another name for a B-way set associative cache with one set. Figure 8.11 shows the SRAM array of a fully associative cache with eight blocks.

How many cache line a fully associative cache has?

4 cache lines
For a 4-way associative cache each set contains 4 cache lines. Each cache line consists of a “tag” and a “data” field. There is also a “valid” bit, which is not shown. The tag portion of the request address is compared to all of the tag fields in the selected set.

What is set in set associative mapping?

In k-way set associative mapping, Cache lines are grouped into sets where each set contains k number of lines. A particular block of main memory can map to only one particular set of the cache. However, within that set, the memory block can map to any freely available cache line.

What is fully associative cache mapping?

Fully Associative Mapping is a cache mapping technique that allows to map a block of main memory to any freely available cache line.

What are cache sets?

— The cache is divided into groups of blocks, called sets. — Each memory address maps to exactly one set in the cache, but data may be placed in any block within that set. Here are several possible organizations of an eight-block cache.

What is an associative cache?

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 big is the two way set associative cache?

A two-way set-associative cache has lines of 16 bytes and a total size of 8 kbytes. The 64-Mbyte main memory is byte addressable. Show the format of main memory addresses. There are a total of 8 kbytes/16 bytes = 512 lines in the cache.

How many blocks are there in the cache?

The cache is divided into 16 sets of 4 lines each. Therefore, 4 bits are needed to identify the set number. Main memory consists of 4K = 212 blocks. Therefore, the set plus tag lengths must be 12 bits and therefore the tag length is 8 bits. Each block contains 128 words.

How is data copied from main memory to cache?

When a requested word is not in the cache, a new line of data is copied from main memory into the cache. Assuming a four-way set, bits A10 to A4 of the address from the microprocessor indicate the cache location where the new line is to be stored, but which of the four lines in the set stored at that location is to be replaced?

How is the location of the cache determined?

Assuming a four-way set, bits A10 to A4 of the address from the microprocessor indicate the cache location where the new line is to be stored, but which of the four lines in the set stored at that location is to be replaced? This decision must be made entirely by hardware because software will be much too slow.