What is Memory Cache?

Memory cache functions as a temporary storage area within the application's memory. It acts as a high-speed data repository for data that is frequently accessed, making retrieval much faster without the need to repeatedly access the original source, such as a database or an external API. By utilizing memory caching, applications can minimize latency and enhance response times, ultimately improving performance.

Benefits of Memory Cache

1. Enhanced Performance: By keeping frequently accessed data in memory, memory caching minimizes the need for expensive disk I/O operations, leading to quicker data retrieval.
2. Reduced Resource Load: Caching data in memory lessens the demand on backend resources, including databases or external services, by fulfilling requests directly from memory.
3. Improved Scalability: Memory caching aids in scaling applications more efficiently by decreasing the load on backend systems, enabling them to handle a larger volume of requests.

Implementing Memory Cache in .NET Core

In .NET Core, the MemoryCache class offers a straightforward yet robust method for integrating memory caching into your applications. Here is a basic example of how to utilize MemoryCache:

using Microsoft.Extensions.Caching.Memory;

using System;

public class CacheManager

{

private readonly IMemoryCache _memoryCache;

public CacheManager(IMemoryCache memoryCache)

{

_memoryCache = memoryCache;

}

public T GetOrCreate(string key, Func<T> createItem, TimeSpan expirationTime)

{

if (!_memoryCache.TryGetValue(key, out T cachedItem))

{

cachedItem = createItem();

if (cachedItem != null)

{

var cacheEntryOptions = new MemoryCacheEntryOptions()

.SetAbsoluteExpiration(expirationTime);

_memoryCache.Set(key, cachedItem, cacheEntryOptions);

}

}

return cachedItem;

}

}

In this example, we define a CacheManager class that encapsulates caching functionalities. The GetOrCreate method attempts to retrieve an item from the cache; if it’s not found, it calls the provided createItem function, caches the result, and returns it.

Singleton Pattern for Memory Cache

To ensure a single instance of the CacheManager is used throughout the application, we can apply the Singleton pattern. Here’s how to adjust our CacheManager class for this pattern:

public sealed class CacheManagerSingleton

{

private static readonly Lazy<CacheManagerSingleton> lazy =

new Lazy<CacheManagerSingleton>(() => new CacheManagerSingleton());

public static CacheManagerSingleton Instance { get { return lazy.Value; } }

private readonly IMemoryCache _memoryCache;

private CacheManagerSingleton()

{

_memoryCache = new MemoryCache(new MemoryCacheOptions());

}

public T GetOrCreate(string key, Func<T> createItem, TimeSpan expirationTime)

{

if (!_memoryCache.TryGetValue(key, out T cachedItem))

{

cachedItem = createItem();

if (cachedItem != null)

{

var cacheEntryOptions = new MemoryCacheEntryOptions()

.SetAbsoluteExpiration(expirationTime);

_memoryCache.Set(key, cachedItem, cacheEntryOptions);

}

}

return cachedItem;

}

}

In this implementation, the CacheManagerSingleton class is sealed to prevent inheritance, and the constructor is private to disallow external instantiation. The Instance property grants access to the single instance of the class.

Conclusion

Memory caching is an invaluable tool for boosting performance in .NET Core applications. By retaining frequently accessed data in memory, applications can lower latency, ease the load on backend resources, and enhance scalability. The Singleton pattern ensures a singular cache manager instance is utilized across the application, optimizing caching efficiency.

Integrating memory caching into your .NET Core applications can lead to remarkable performance gains, making it a crucial technique for developers aiming to create fast and responsive software solutions.