We solved this issue by combining Lazy<T> with AddOrGetExisting to avoid a need for a lock object completely. Here is a sample code (which uses infinite expiration): public T GetFromCache<T>(string key, Func<T> valueFactory) { var newValue = new Lazy<T>(valueFactory); // the line belows returns existing item or adds the new value if it doesn’t exist … Read more
As per the documentation, you have a few options here: If your filters have dependencies that you need to access from DI, there are several supported approaches. You can apply your filter to a class or action method using one of the following: ServiceFilterAttribute TypeFilterAttribute IFilterFactory implemented on your attribute ServiceFilter or TypeFilter attributes If … Read more
I recently went through this myself as well. Considering an in memory cache will be process specific (not shared across multiple instances of a website or native business app or multiple servers) there is really no benefit to having multiple MemoryCache instances except for code organizational reasons (which can be achieved in other ways). The … Read more
Wow, so I just spent entirely too much time digging around in the CLR with reflector, but I think I finally have a good handle on what’s going on here. The settings are being read in correctly, but there seems to be a deep-seated problem in the CLR itself that looks like it will render … Read more
Add does nothing (returns false) if there is already a value for that key. Set does an insert or update, as necessary. Remove + Add would leave a gap in the middle when another thread querying that key would get no clue (Set does not; the swap is typically atomic); as such, while Set has … Read more
The default MS-provided MemoryCache is entirely thread safe. Any custom implementation that derives from MemoryCache may not be thread safe. If you’re using plain MemoryCache out of the box, it is thread safe. Browse the source code of my open source distributed caching solution to see how I use it (MemCache.cs): https://github.com/haneytron/dache/blob/master/Dache.CacheHost/Storage/MemCache.cs
Dispose the existing MemoryCache and create a new MemoryCache object.
This is my 2nd iteration of the code. Because MemoryCache is thread safe you don’t need to lock on the initial read, you can just read and if the cache returns null then do the lock check to see if you need to create the string. It greatly simplifies the code. const string CacheKey = … Read more