WOW is akin to CSCAN, since it destages in essentially the same order as CSCAN. However, WOW is different from CSCAN in that it skips destage of data that have been recently written to in the hope that that are likely to be written to again. WOW generally will have a higher hit ratio than CSCAN at the cost of an increased gap between consecutive destages.
WOW is akin to LRW in that it defers write groups that have been recently written. Similarly, WOW is akin to CLOCK in that upon a write hit to a write group a new life is granted to it until the destage pointer returns to it again. WOW is different from CLOCK in that the new write groups are not inserted immediately behind the destage pointer as CLOCK would but rather in their sorted location. Thus, initially, CLOCK would always grant one full life to each newly inserted write group, whereas WOW grants on an average half that much time. WOW generally will have a significantly smaller gap between consecutive destages than LRW at the cost of a generally lower hit ratio.