Function usage

tools/benchmark/node_write_bench.cpp:44–47

};

static void usage(const char* program) {
    std::cerr << "Usage: " << program << " [--seconds N] [--preserve-db] [thread_count ...]\n"
              << "Example: " << program << " --seconds 30 --preserve-db 1 2 4 8\n";
}

static Config parseArgs(int argc, char** argv) {
    Config config;