Which of the following commands should be used to observe the number of system calls per second? （）

单项选择题AllofthefollowingtypesofstatisticsarereportedbytheiostatcommandtoolEXCEPT:（）.

A. Free memory
B. CPU statistics 
C. Disk statistics 
D. Terminal statistics

单项选择题To examine the Exhibit, press the Exhibit button. Which option would produce this output from the errpt command? （）

A. errpt -t 
B. errpt -a 
C. errpt -D 
D. errpt

单项选择题AnSSAdiskthatispartofthemirroredvolumegroupneedstobereplaced.Whichofthefollowingproceduresshouldbeperformedbeforethediskisphysicallyabletobereplaced?（）

A.reducevg, rmdev, syncvg 
B.rmlvcopy, exportvg, rmdev 
C.rmlvcopy, reducevg, rmdev 
D.No action is required since SSA is a Hot Swap device and is mirrored

单项选择题Whichofthefollowingcommandsshouldbeusedtoclearallentriesfromtheerrorlog?（）

A. errpt -d S 0 
B. errclear 0 
C. errpt -d H 0 
D. errclear -d H 0 

单项选择题While a user is compiling a C program,  vmstat 120 10  is run to determine the cause of a performance problem.  Using the vmstat output as shown in the exhibit, which of the following conclusions is most appropriate to draw?（）

A. There is a file I/O bottleneck.
B. There are too many open files. 
C. There appears to be a buffer shortage. 
D. There is a paging space I/O bottleneck.