CPU usage is misreported.

Currently "0 CPU" means "no CPU metric received in the previous ProfileEvents packet". But there can be many ProfileEvents packets and only a few with CPU increment.

That's why the CPU metric shows something weird like:
```
0
0
0
0
0
1234
0
0
0
...
```

This is unbearable, and the CPU metric should be either fixed or removed altogether.
UInt64 max   = 0;
    };
    MemoryUsage getMemoryUsage() const;
    
    
    bool show_progress_bar = false;
    
    
    size_t written_progress_chars = 0;
    
    
    Progress progress;
    
    Stopwatch watch;
    bool write_progress_on_update = false;
    std::unordered_map<String, double> host_cpu_usage;
    HostToThreadTimesMap thread_data;
    
    
    
    
    
    
    
    
    mutable std::mutex profile_events_mutex;
    mutable std::mutex progress_mutex;
};
}