Hi, Morten Brix Pedersen wrote: > int main() > { > string test = "IUHASISAHDNI"; > > vector<string> vec; > for (int i = 0; i <= 500000; ++i) { > string newstr; > test += "NAWNASDKJNKNN"; > newstr = test; String assignments are threadsafe now with gcc-3.0, so that will have an additional overhead. As already mentioned it's very important to enable optimization for c++ code. bye, Roman