$ time ./llil3m big1.txt big2.txt big3.txt  >f.tmp
llil3m (fixed string length=6) start
   - openmp version
get_properties     CPU  time : 2.40089 secs
vector copy        CPU  time : 0.544294 secs
vector stable sort CPU  time : 5.84981 secs
write  stdout      CPU  time : 0.805509 secs
total              CPU  time : 9.6006 secs
total             wall clock : 4 secs

real    0m4.713s
user    0m9.238s
sys     0m0.679s