An access request that includes a combination of a file identifier and an offset value is received. If the page cache does not contain the page indexed by the combination, then the file system is accessed and the offset value is mapped to a disk location. The file system can access a block map to identify the location. A table (e.g., a shared location table) that includes entries (e.g., locations) for pages that are shared by multiple files is accessed. If the aforementioned disk location is in the table, then the requested page is in the page cache and it is not necessary to add the page to the page cache. Otherwise, the page is added to the page cache.