Sample test files for directed weighted graphs

I'm trying to test some graph shortest-path algorithms and evaluate the execution time when a graph gets bigger and more complex. The inputs are weighted directed graphs, with source destination weight format as bellow.

Where can I find a database of such graph files? Do you know a base for such files? I'm not sure randomly generating myself will be a good choice.

    1 2 3
    2 3 4
    4 5 2
    5 6 6
    7 8 8
    8 9 1
    1 4 7
    2 5 2
    3 6 5
    4 7 3
    5 8 4
    6 9 9
    9 1 2