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What is stale data in cache?
Stale data is an artifact of caching, in which an object in the cache is not the most recent version committed to the data source. To avoid stale data, implement an appropriate cache locking strategy. By default, EclipseLink optimizes concurrency to minimize cache locking during read or write operations.
How do you deal with stale cache?
Stale Cache Processing Configure the Rebuild Stale Cache job to automatically rebuild stale cache on a scheduled basis to minimize the delivery of outdated content. Scheduling this task to run frequently (for example, every two to five minutes) will maximize content freshness and minimize processing time.
What is a write behind cache?
Write-behind is a caching strategy in which the cache layer itself connects to the backing database. This means that your applications need only ever connect to your cache layer, and the cache then reads from or updates the backing database as needed.
Why do I need to use the Cache Aside Pattern?
Implementing the Cache-Aside pattern doesn’t guarantee consistency between the data store and the cache. An item in the data store can be changed at any time by an external process, and this change might not be reflected in the cache until the next time the item is loaded.
How to deal with stale data in Cache?
Suppose the following sequence happens: client A reads from the cache and got a miss. client A reads from the database. client B updates the same entry in the database. client B deletes the (non-existent) cache entry. client A puts the (stale) entry in the cache. client C will then read the stale data in the cache.
What should be the expiration period of Cache Aside?
For cache-aside to be effective, ensure that the expiration policy matches the pattern of access for applications that use the data. Don’t make the expiration period too short because this can cause applications to continually retrieve data from the data store and add it to the cache.
What happens if there is no match in Cache?
If a matching item is found, it’s returned. If there’s no match in the cache, the GetMyEntityAsync method retrieves the object from a data store, adds it to the cache, and then returns it. The code that actually reads the data from the data store is not shown here, because it depends on the data store.