A method, performed by a Memory Availability Managing Module, for managing availability of memory pages, wherein the memory pages are comprised in a set of memory blades (105, 106, 107), wherein a hardware system comprises the set of memory blades (105, 106, 107) and a set of computing pools (102, 103, 104), wherein the set of memory blades (105, 106, 107) and the set of computing pools (102, 103, 104) are interconnected with each other, wherein the set of computing pools (102, 103, 104) comprises computing units, wherein at least one operating system executes on the hardware system, wherein the Memory Availability Managing Module is independent of the operating system, wherein the method comprises: receiving a message comprising a request or information about a request for allocation of at least one memory page of the memory pages to said at least one operating system, wherein the message comprises an indication about a level of availability for said at least one memory page wherein the level of availability represents the number of copies of said at least one memory page and a maximum latency between said at least one memory page and a subset of the computing units, on which the operating system is executable; translating the indication about availability to a set of memory blade parameters, wherein the set of memory blade parameters identifies at least one memory blade (105, 106, 107) of the set of memory blades (105, 106, 107), wherein said at least one memory page is allocated to said at least one memory blade (105, 106, 107); generating, based on the set of memory blade parameters, address mapping information for said at least one memory page, wherein the address mapping information includes a logical address of said at least one memory page mapped to at least two physical memory addresses of said at least one memory blade (105, 106, 107); and providing at least some of the address mapping information for use when access to said at least one memory page is requested, wherein said at least some of the address mapping information comprises one of said at least two physical memory addresses. receiving a message comprising a request or information about a request for allocation of at least one memory page of the memory pages to said at least one operating system, wherein the message comprises an indication about a level of availability for said at least one memory page wherein the level of availability represents the number of copies of said at least one memory page and a maximum latency between said at least one memory page and a subset of the computing units, on which the operating system is executable; translating the indication about availability to a set of memory blade parameters, wherein the set of memory blade parameters identifies at least one memory blade (105, 106, 107) of the set of memory blades (105, 106, 107), wherein said at least one memory page is allocated to said at least one memory blade (105, 106, 107); generating, based on the set of memory blade parameters, address mapping information for said at least one memory page, wherein the address mapping information includes a logical address of said at least one memory page mapped to at least two physical memory addresses of said at least one memory blade (105, 106, 107); and providing at least some of the address mapping information for use when access to said at least one memory page is requested, wherein said at least some of the address mapping information comprises one of said at least two physical memory addresses.