Write Bytes Paging/sec is the rate at which the Redirector is attempting to write bytes changed in the pages being used by ...

Write Bytes Paging/sec is the rate at which the Redirector is attempting to write bytes changed in the pages being used by applications.  The program data changed by modules (such as programs and libraries) that were loaded over the network are 'paged out' when no longer needed.  Other output pages come from the file system cache (see Write Bytes Cache/sec).