单项选择题
A. sar
B. pstat
C. iostat
D. filemon
单项选择题 Whichofthefollowingcommandsshouldbeusedtoshowhowmuchdataisreadfromorwrittentoaparticularlogicalvolume，giventhereareseveralotherlogicalvolumesonthesamedisk？（）
单项选择题 WhichofthefollowingcommandsshouldbeusedtomonitordiskutilizationduringthetimeasystemisexperiencingadiskI/Operformanceproblem？（）
单项选择题 Afterrunningthevmstatcommand，whichofthefollowingwouldmostlikelycausethevalueintheblockedcolumntobeunusuallyhigh？（）