The present invention provides a method and system of performing a current filesystem backup with respect to a previous filesystem backup using directorywise hardlinking for a computer filesystem. In an exemplary embodiment, the method and system include (1) identifying all largest unchanged subtrees in the previous filesystem backup with respect to a current computer filesystem and (2) creating directorywise hardlinks in the current filesystem backup to the all largest unchanged subtrees. In an exemplary embodiment, the creating includes for each of the largest unchanged subtrees, forming a first pointer from the current filesystem backup to the each of the largest unchanged subtrees. In a further embodiment, the creating includes for each of the largest unchanged subtrees, establishing a second pointer from the each of the largest unchanged subtrees to a directory in the current filesystem backup that corresponds to the first pointer.