[Bug libstdc++/54075] [4.7.1] unordered_map 3x slower than 4.6.2

[likan_999.student at sina dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54075

--- Comment #5 from likan_999.student at sina dot com 2012-07-24 00:17:10 UTC ---
@Paolo Carlini: can you talk more about how to experiment with max_load_factor?
 As long as I use the same max_load_factor for 4.6 and 4.7, I can still see the
performance difference (3x slower is the best result):

max_load_factor  gcc-4.6.2 gcc-4.7.1
0.2                      1.600s      7.650s
0.5                      1.125s      4.251s
1.0                      1.004s      3.378s
2.0                      0.914s      20.471s
5.0                      0.917s      29.132s