How can I invalidate the file system cache?

Question

I want to measure/optimize the "cold boot" startup performance of an application, and it\'s difficult to do this without an actual reboot, which is obviously not a

Answer 1

This solution worked great: Clear file cache to repeat performance testing

More specifically, I'm doing this:

// Open with FILE_FLAG_NO_BUFFERING
auto hFile = CreateFile(path.c_str(),
                        GENERIC_READ,
                        FILE_SHARE_READ,
                        nullptr,
                        OPEN_EXISTING,
                        FILE_FLAG_NO_BUFFERING,
                        nullptr);

/// Check
if (hFile == INVALID_HANDLE_VALUE){
    //_tprintf(TEXT("Terminal failure: unable to open file \"%s\" for read.\n"), argv[1]);
    cout << "error" << endl;
    return;
}

// Close
CloseHandle(hFile);

// Now open file with regular C++ API, and caching disabled
ifstream file(path, ios::binary | ios::ate);