Fast hash lookup

[mono12]

Hi!

I am using c++ stl hash_maps in my program. My hash_map is ~1million entries of <int,T*>. The default hash function is very slow, ~60m hash_map lookups are taking several hours.
Does any one have a suggestion for faster hash lookup?

Thanks!

[weaknessforcats]

Have you compared this to a regular map?

Or, have to tried to write your own compare function?

With this many entries you might also look at a chain-link table.

[gpraghuram]

Hi!

I am using c++ stl hash_maps in my program. My hash_map is ~1million entries of <int,T*>. The default hash function is very slow, ~60m hash_map lookups are taking several hours.
Does any one have a suggestion for faster hash lookup?

Thanks!

Try to use bit wise operators in the compare function .
I think it will have some improvements

Raghuram