[Beowulf] Time measurement

[ThanhVu H. Nguyen - Gmail]

Hi, just wondering what the standard way of measure the execution time
?  

2 methods I thought about are: 

1) /usr/bin/time  prog   : this includes all the communcation, i/o ,
loading overhead etc

2) include start_time , end_time code in the program : this won't
include the communication , i/o , loading etc overhead.

what method is usually used ?  thanks  

tvn,

ThanhVu H. Nguyen