How to properly implement caching with IMemoryCache in an ASP.NET Core application to improve performance?
Does anyone know how to I'm trying to debug I'm relatively new to this, so bear with me. I'm working on an ASP.NET Core 6 MVC application where I've been trying to optimize performance via caching. I decided to use `IMemoryCache` for this purpose, but I'm running into some unexpected behaviors. My goal is to cache the results of a database call to avoid hitting the database repeatedly for the same data. I've set up my `IMemoryCache` like this in my controller: ```csharp public class ProductsController : Controller { private readonly IMemoryCache _cache; private readonly ApplicationDbContext _context; public ProductsController(IMemoryCache cache, ApplicationDbContext context) { _cache = cache; _context = context; } public async Task<IActionResult> Index() { var cacheKey = "productList"; if (!_cache.TryGetValue(cacheKey, out List<Product> products)) { products = await _context.Products.ToListAsync(); var cacheEntryOptions = new MemoryCacheEntryOptions() .SetSlidingExpiration(TimeSpan.FromMinutes(5)); _cache.Set(cacheKey, products, cacheEntryOptions); } return View(products); } } ``` The caching seems to work initially, as I see a performance improvement. However, after a while, the data becomes outdated, and I'm not sure how to handle cache invalidation effectively. On one occasion, after updating the products in the database, I found that the cached list did not reflect those changes. I tried using `MemoryCacheEntryOptions` with a `AbsoluteExpiration` policy as follows: ```csharp var cacheEntryOptions = new MemoryCacheEntryOptions() .SetAbsoluteExpiration(TimeSpan.FromMinutes(30)); ``` However, this still doesn't seem to help in ensuring that stale data is replaced when I update the database. I’ve also considered using a separate service layer to handle caching, but I'm unsure how to proceed without over-complicating the architecture. Is there a best practice for cache invalidation that I might be missing? How can I effectively ensure that my cache reflects the latest data without causing performance issues? I'm working on a application that needs to handle this. What am I doing wrong? I'm using Csharp 3.11 in this project. What would be the recommended way to handle this? Thanks for any help you can provide!