`total_memory_tracker.setOrRaiseHardLimit(...);` in `ConfigReloader` callback (see `Server.cpp`).
{
    Poco::trimInPlace(path);
    if (path.empty())
        throw Exception("path configuration parameter is empty", ErrorCodes::INVALID_CONFIG_PARAMETER);
    if (path.back() != '/')
        path += '/';
    return std::move(path);
}
static std::string getUserName(uid_t user_id)
{
    
    auto buffer_size = sysconf(_SC_GETPW_R_SIZE_MAX);
    if (buffer_size <= 0)
        buffer_size = 1024;
    std::string buffer;
    buffer.reserve(buffer_size);
    struct passwd passwd_entry;
    struct passwd * result = nullptr;
    const auto error = getpwuid_r(user_id, &passwd_entry, buffer.data(), buffer_size, &result);
    if (error)
        throwFromErrno("Failed to find user name for " + toString(user_id), ErrorCodes::FAILED_TO_GETPWUID, error);
    else if (result)
        return result->pw_name;
    return toString(user_id);
}
Poco::Net::SocketAddress makeSocketAddress(const std::string & host, UInt16 port, Poco::Logger * log)