What is the test for dismissing a case for failure to prosecute under Rule 41(b)?

Prior to dismissing for failure to prosecute under Rule 41(b), the court must consider the factors outlined in Henderson v. Duncan, 779 F.2d 1421, 1423 (9th Cir. 1986), namely: "(1) the public's interest in expeditious resolution of litigation; (2) the court's need to manage its docket; (3) the risk of prejudice to the defendants; (4) the public policy favoring disposition of cases on their merits; and (5) the availability of less drastic sanctions." "The district court has the inherent power sua sponte to dismiss a case for lack of prosecution." Id.