Profiling C++ code on Linux: how to find bottlenecks and speed up the program?

Hello everyone! I've been writing in C++ for quite a while, but I've never seriously done profiling. Now I've run into a problem: my program, which processes large amounts of data, is running too slowly. It parses CSV files, performs some mathematical calculations, and writes the results to a binary file. On a test set of 500 MB of data, execution takes about 4 minutes, but I'd like to get it down to 30 seconds.\n\nHere's a simplified example of what I'm doing:\n\n```cpp\n#include \n#include \n#include \n#include \n\nstd::vector processData(const std::vector& input) {\n std::vector result;\n result.reserve(input.size());\n for (size_t i = 0; i < input.size(); ++i) {\n double val = input[i];\n // Some computations