Does using NSCache to cache image downloads waste memory as NSURLSession ready caches?

Question

I know NSURLSession uses NSURLCache to cache HTTP responses, so if I use NSCache to cache image downloads due to its own advantages, am I having two copies in memory for each cache, and thus being wasteful?

If so, how do I stop NSURLSession from caching in memory automatically? (I still want the persistent store caching though.)

Answer 1

You can create custom NSURLCache object with zero or just few bytes of memory. And than set it as shared cache to prevent memory usage.

NSURLCache * cache = [[NSURLCache alloc]initWithMemoryCapacity:1024 diskCapacity:1024*1024 diskPath:nil];
[NSURLCache setSharedURLCache:cache];

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