memorycache

I'd like to add caching capabilities to my application using the System.Runtime.Caching namespace, and would probably want to use caching in several places and in different contexts. To do so, I want to use several MemoryCache instances. However, I see here that using more than one instance of MemoryCache is discouraged: MemoryCache is not a singleton, but you should create only a few or potentially only one MemoryCache instance and code that caches items should use those instances. How would multiple MemoryCache instances affect my application? I find this kind of weird because it seems to me

I'm trying to use a MemoryCache in .net 4.5 to keep track of and automatically update various items, but it seems like no matter what I set as an AbsoluteExpiration it will always only expire in 15 seconds or more. I want the cache items to expire every 5 seconds, but it always expires in at least 15 seconds, and if I move the expiration time out, it will end up being something like 15 seconds + my refresh interval, but never less than 15 seconds. Is there some internal timer resolution that I'm not seeing? I looked through a bit of the reflected System.Runtime.Caching.MemoryCache code and

I assume this code has concurrency issues: const string CacheKey = "CacheKey"; static string GetCachedData() { string expensiveString =null; if (MemoryCache.Default.Contains(CacheKey)) { expensiveString = MemoryCache.Default[CacheKey] as string; } else { CacheItemPolicy cip = new CacheItemPolicy() { AbsoluteExpiration = new DateTimeOffset(DateTime.Now.AddMinutes(20)) }; expensiveString = SomeHeavyAndExpensiveCalculation(); MemoryCache.Default.Set(CacheKey, expensiveString, cip); } return expensiveString; } The reason for the concurrency issue is that multiple threads can get a null key and

I’m working with the .NET 4.0 MemoryCache class in an application and trying to limit the maximum cache size, but in my tests it does not appear that the cache is actually obeying the limits. I'm using the settings which, according to MSDN , are supposed to limit the cache size: CacheMemoryLimitMegabytes : The maximum memory size, in megabytes, that an instance of an object can grow to." PhysicalMemoryLimitPercentage : "The percentage of physical memory that the cache can use, expressed as an integer value from 1 to 100. The default is zero, which indicates that MemoryCache instances manage

I have created a cache using the MemoryCache class. I add some items to it but when I need to reload the cache I want to clear it first. What is the quickest way to do this? Should I loop through all the items and remove them one at a time or is there a better way? Dispose the existing MemoryCache and create a new MemoryCache object. The problem with enumeration The MemoryCache.GetEnumerator() Remarks section warns: "Retrieving an enumerator for a MemoryCache instance is a resource-intensive and blocking operation. Therefore, the enumerator should not be used in production applications." Here

I have a problem with an MVC 3 application that is using the new .NET 4 System.Runtime.Caching MemoryCache. I notice that after a seemingly unpredictable time, it stops caching stuff, and acts like it's empty. Consider this bit of code that I took straight from a test View in ASP.NET MVC: MemoryCache.Default.Set("myname","fred", new CacheItemPolicy() { SlidingExpiration = new TimeSpan(0,5,0) }); Response.Write(MemoryCache.Default["myname"]); When it's working, predictably "fred" gets printed. However, when the problem starts to occur, despite the Set() , the value of MemoryCache.Default[