Provided herein a method for allocating storage space using a buddy allocator, the method including receiving, by a buddy allocator, a block allocation request from a space allocation requestor, selecting, by the buddy allocator, a first buddy in response to the block allocation request, wherein the first buddy is one of a plurality of buddies, checking, by the buddy allocator, whether blocks of the first buddy include a first spare storage space to which storage space corresponding to the block allocation request is allocated, allocating, by the buddy allocator, the storage space to the blocks of the first buddy when it is checked that the blocks of the first buddy include the first spare storage space, and deallocating, by the buddy allocator, excess storage space of allocated storage space when a size of the allocated storage space is greater than the storage corresponding to the block allocation request, wherein the excess storage space is not corresponding to the block allocation request.