How do you maintain cache coherence?

There are two general strategies for dealing with writes to a cache:

1. Write-through – all data written to the cache is also written to memory at the same time.
2. Write-back – when data is written to a cache, a dirty bit is set for the affected block. The modified block is written to memory only when the block is replaced.

What is cache coherence and how is it eliminated?

Cache coherence refers to the concept of shared resource data being stored in various local caches uniformly at the same time. There are two ways cache coherence can be eliminated using the hardware approach – directory based and snooping.

What are the different types of cache coherence?

The two most common types of coherence that are typically studied are Snooping and Directory-based. Each has its own benefits and drawbacks. Snooping protocols tend to be faster, if enough bandwidth is available, since all transactions are a request/response seen by all processors.

What is cache coherence and Mesi protocol?

The MESI protocol is an Invalidate-based cache coherence protocol, and is one of the most common protocols that support write-back caches. There is always a dirty state present in write back caches that indicates that the data in the cache is different from that in main memory.

What is the cache coherence compare different types of cache coherence?

Cache coherence is the discipline that ensures that changes in the values of shared operands are propagated throughout the system in a timely fashion. All processors see exactly the same sequence of changes of values for each separate operand.

What do you mean by cache coherence problem explain in detail?

The Cache Coherence Problem is the challenge of keeping multiple local caches synchronized when one of the processors updates its local copy of data which is shared among multiple caches. This cache miss forces the second core’s cache entry to be updated.