What is CacheEntryOptions in .NET Core

Caching plays a crucial role in enhancing the performance and scalability of applications. In .NET Core, MemoryCache class enables storing frequently accessed data in memory, facilitating quick retrieval. To tailor cached item behavior, developers can utilize CacheEntryOptions. This post delves into CacheEntryOptions and its role in customizing caching behavior in .NET core applications.

What are CacheEntryOptions?

CacheEntryOptions, found in the Microsoft.Extensions.Caching.Memory namespace, empowers developers to configure various settings related to cached items in MemoryCache. These options allow control over properties such as expiration time, priority, and post-eviction callbacks for cached items.

Key Properties of CacheEntryOptions

1. AbsoluteExpiration and AbsoluteExpirationRelativeToNow:These properties allow specifying when a cached item should expire, either at an absolute time or after a certain duration from its addition to the cache.
2. SlidingExpiration:SlidingExpiration enables defining a time window after which the cached item expires if not accessed. Each access to the item resets the sliding window.
3. Priority:CacheEntryOptions lets you set the priority of cached items, affecting their likelihood of being removed from the cache upon expiration or when the cache needs space for new items.
4. Size:With CacheEntryOptions, it's possible to set the size of cached items, which proves useful in memory-limited caches for controlling item sizes and preventing excessive memory usage.
5. PostEvictionCallbacks:Post-eviction callbacks allow registering a delegate that executes when a cached item is evicted from the cache. This is beneficial for performing cleanup actions or logging when an item is removed.

Using CacheEntryOptions in .NET Core:

To use CacheEntryOptions, create an instance of this class and set the desired properties. Then, pass the CacheEntryOptions object to the MemoryCache.Set method while adding an item to the cache.

Example of CacheEntryOptions usage:

using Microsoft.Extensions.Caching.Memory;
// Create an instance of CacheEntryOptions
var cacheEntryOptions = new MemoryCacheEntryOptions
{
    AbsoluteExpirationRelativeToNow = TimeSpan.FromMinutes(30),
    Priority = CacheItemPriority.High,
    PostEvictionCallbacks =
    {
        new PostEvictionCallbackRegistration
        {
            EvictionCallback = (key, value, reason, state) =>
            {
                // Perform post-eviction cleanup or logging here
                Console.WriteLine($"Cached item with key '{key}' was evicted due to '{reason}'.");
            }
        }
    }
};

// Add an item to the cache with CacheEntryOptions
memoryCache.Set("myCacheKey", myCachedData, cacheEntryOptions);

CacheEntryOptions in .NET Core offer a robust approach to control cached item behavior within MemoryCache. Leveraging these options allows fine-tuning caching behavior, setting expiration policies, handling evictions, and optimizing memory usage. Effective caching can significantly enhance the performance of your .NET Core applications, particularly when dealing with frequently accessed data.

Remember to choose a caching strategy carefully based on your application's requirements to ensure optimal performance and mitigate potential memory-related issues.

Happy coding!! 😊