Write back: Write update goes to cache, data is saved in the cache, and acknowledge is send immediately.Data is written to the cache when there is the first cache miss. Write around: Write request goes around the cache straight to DB and acknowledge is sent back, data is not sent to cache.Write is considered successful only iff data is written successfully in the cache and in DB. Write through: whenever any “ write” request comes, it will come through the cache to the DB.Our cache should able to sustain 50K to 1M query per second.We want to save a huge amount of data, size near to TerraByte.
Controls such as TTLs (Time to live) can be applied to expire the data accordingly. A cache miss occurs when the data fetched was not present in the cache. A successful cache results in a high hit rate which means the data was present when fetched. When implementing a cache layer, it’s important to understand the validity of the data being cached. Caching is used in every layer of technology e.g: operating systems, CDN, DNS, in many applications like searching, also used in games to increase media content performance. RAM provides faster i/o operation and reduces latency. The caching system’s data is actually stored in the faster access hardware like RAM. Caching allows you to efficiently reuse previously retrieved or computed data. In computing, a cache is a high-speed data storage layer that stores a subset of data, typically transient in nature, so that future requests for that data are served up faster than is possible by accessing the data’s primary storage location.