. For example, many memory blocks contain code or unchanging data which is read in from the disk. It would make no sense to swap these blocks back to disk, since the data is already there. Instead, one can mark a block &quot;discardable.&quot; This indicates that when the block is unlocked, the memory manager can, at will, discard the block. If a process attempts to lock a block which has been discarded, the memory manager will return an error. The application can then &quot;re-allocate&quot; memory for tha