What are some examples of cache consistency problems?

What are some examples of cache consistency problems?

Cache consistency problems occur when multiple caches have different versions of the same data. For example, if one user updates a record in a database, but other users see an outdated version due to stale cache data.

Can you give me a specific scenario where this happens?

Sure! Imagine an online shopping site where two users add the same item to their cart. If one user checks out and the cache isn't updated, the second user might still see the item as available, leading to overselling.

How can these problems be resolved?

There are several strategies, such as using cache invalidation techniques, implementing a write-through cache, or employing distributed locking mechanisms to ensure data consistency.

What are the trade-offs of these solutions?

Each solution has its trade-offs. For instance, cache invalidation can lead to increased latency, while distributed locking can create bottlenecks. It's essential to balance performance and consistency based on the application's needs.