AnAIXsystem，whichisrunningadatabase，ishavingperformanceissueswithI\/Owriting.TheDBAhasprovidednumbersfortheHIGHandLOWwatermarksforpendingfilewrites，whichwilloptimizethesystemforbestperformance.Tosetthesenumbers，whichofthefollowingcommandswouldbeused？（）
A.perfmon-h30-l25
B.chdev
C.no-o
D.smitchgsys
参考答案：D
