Re: [PATCH - RFC] [1/5] 64-bit network statistics - generic net

[Jeff Garzik]

Jeff Sipek wrote:
> +	spinlock_t	rx_packets;
> +	spinlock_t	tx_packets;
> +	spinlock_t	rx_bytes;
> +	spinlock_t	tx_bytes;
> +	spinlock_t	rx_errors;
> +	spinlock_t	tx_errors;
> +	spinlock_t	rx_dropped;
> +	spinlock_t	tx_dropped;
> +	spinlock_t	multicast;
> +	spinlock_t	collisions;
> +	spinlock_t	rx_length_errors;
> +	spinlock_t	rx_over_errors;
> +	spinlock_t	rx_crc_errors;
> +	spinlock_t	rx_frame_errors;
> +	spinlock_t	rx_fifo_errors;
> +	spinlock_t	rx_missed_errors;
> +	spinlock_t	tx_aborted_errors;
> +	spinlock_t	tx_carrier_errors;
> +	spinlock_t	tx_fifo_errors;
> +	spinlock_t	tx_heartbeat_errors;
> +	spinlock_t	tx_window_errors;
> +	spinlock_t	rx_compressed;
> +	spinlock_t	tx_compressed;

That's a fat daddy list of locks you got there.

> +	NETSTAT_TYPE	_rx_packets;		/* total packets received	*/
> +	NETSTAT_TYPE	_tx_packets;		/* total packets transmitted	*/
> +	NETSTAT_TYPE	_rx_bytes;		/* total bytes received 	*/
> +	NETSTAT_TYPE	_tx_bytes;		/* total bytes transmitted	*/
> +	NETSTAT_TYPE	_rx_errors;		/* bad packets received		*/
> +	NETSTAT_TYPE	_tx_errors;		/* packet transmit problems	*/
> +	NETSTAT_TYPE	_rx_dropped;		/* no space in linux buffers	*/
> +	NETSTAT_TYPE	_tx_dropped;		/* no space available in linux	*/
> +	NETSTAT_TYPE	_multicast;		/* multicast packets received	*/
> +	NETSTAT_TYPE	_collisions;

Increasing user-visible sizes arbitrarily breaks stuff.  Having 
config-dependent types like this increases complexity.

Short term, just sample the stats more rapidly.

Long term, I suppose with 10GbE we should start thinking about this. 
Personally, I would prefer to make the standard net device stats 
available in the format already exported by ETHTOOL_GSTATS -- which I 
note uses u64's for its counters, and it's easily extensible.  I 
received a request for this just today, even.

	Jeff

P.S.  Please cc [e-mail] for networking discussions.