./svg_test.sh <-d devname> [-u lvunit ] [-r loop ] [-n lvnum ] 
 [-m metasize] [-a 1/0 active] [-l logfile]
 devname:The LNU device name 
 lvunit: The size (Megabyte) of a lv or pool . optional. default is 16. 
 loop : The loop test number. optional. default is 1 
 lvnum: The number of lv/pool. optional. default is auto calc. 
 if specify it , the final value is min(lvnum, auto) 
 metasize: the meta size of vg, default 256M 
 avtive: active flag of lv 1:active(default) 0 deactive logfile: logfile 

Example: ./svg_test.sh -d /dev/sdb -u 1024 -r 1 -n 2