$ time ./llil4map long* long* long* | cksum
llil4map start
use OpenMP             ( old )     ( new )
memory consumption     36.6 GB     17.5 GB
use boost sort
get properties         12.967s     11.836s
map to vector           3.244s      1.292s
vector stable sort     10.265s     11.025s
write stdout            1.410s      1.364s
total time             27.887s     25.519s
    count lines      970195200
    count unique     295755152
29612263 5038456270

       real time     0m43.973s   0m27.461s
       user         25m08.532s  20m02.479s
       sys           0m55.602s   0m43.250s