C# - Issue with Memory Leak When Using Cached HttpClient in .NET 6 Applications
I've looked through the documentation and I'm still confused about I'm facing a memory leak issue in my .NET 6 application that utilizes a singleton instance of HttpClient for making API calls. The application seems to consume an increasing amount of memory over time, especially when it processes a high volume of requests. I created a simple caching mechanism to store the results of API calls to avoid redundant requests, but I'm worried that the way I'm holding onto the responses is causing unwanted memory retention. Here's a simplified version of my caching logic: ```csharp public class ApiService { private readonly HttpClient _httpClient; private readonly Dictionary<string, string> _cache; public ApiService(HttpClient httpClient) { _httpClient = httpClient; _cache = new Dictionary<string, string>(); } public async Task<string> GetApiResponse(string url) { if (_cache.TryGetValue(url, out var cachedResponse)) { return cachedResponse; } var response = await _httpClient.GetStringAsync(url); _cache[url] = response; return response; } } ``` I use dependency injection to provide the `HttpClient` in my `Startup.cs` like this: ```csharp services.AddSingleton<HttpClient>(); services.AddSingleton<ApiService>(); ``` While this generally works, I'm concerned that the cached responses in the dictionary are not being released, leading to a memory increase. I've tried using `MemoryCache` instead, but it doesn't seem to significantly improve the situation, and I still see the memory usage climbing. I've also used `dotMemory` to analyze the memory usage, and it shows that a large number of entries in the `_cache` dictionary remain allocated even when they are no longer needed. Could the lifetime of `HttpClient` be related to this issue, or is there a better pattern I should be using to manage memory in this scenario? Any insights or recommendations would be appreciated! What's the best practice here?