Simply record the time from entering `main` to start listening sockets.
{
    std::string data_path = getCanonicalPath(server.config().getString("path", DBMS_DEFAULT_PATH));
    std::string logs_path = server.config().getString("logger.log", "");
    if (server.logger().is(Poco::Message::PRIO_TEST))
        server.context()->addWarningMessage("Server logging level is set to 'test' and performance is degraded. This cannot be used in production.");
#if defined(OS_LINUX)
    try
    {
        const char * filename = "/sys/devices/system/clocksource/clocksource0/current_clocksource";
        String clocksource = readString(filename);
        if (clocksource.find("tsc") == std::string::npos && clocksource.find("kvm-clock") == std::string::npos)
            server.context()->addWarningMessage("Linux is not using a fast clock source. Performance can be degraded. Check " + String(filename));
    }
    catch (...)
    {
    }
    try
    {
        const char * filename = "/proc/sys/vm/overcommit_memory";
        if (readNumber(filename) == 2)
            server.context()->addWarningMessage("Linux memory overcommit is disabled. Check " + String(filename));
    }
    catch (...)
    {
    }
    try
    {
        const char * filename = "/sys/kernel/mm/transparent_hugepage/enabled";
        if (readString(filename).find("[always]") != std::string::npos)