The disclosure herein includes caches and a method for managing caches. On account of that some or all elements of the cache could be known, the detail of such elements is omitted provided that such detail has little to do with the features of this disclosure, and that this omission nowhere dissatisfies the specification and enablement requirements. Some or all of the processes of the method for managing caches may be implemented by software and/or firmware and can be performed by the cache or its equivalent. A person having ordinary skill in the art can choose components or steps equivalent to those described in this specification to carry out the present disclosure, which means that the scope of the present disclosure is not limited to the embodiments in the specification.