Jan Ceuleers wrote: > I've been experimenting with the various offload features offered by > some ethernet controllers (drivers: r8169, natsemi, via-velocity) and > exposed through ethtool. > > I must confess not being well-versed in what each feature does, but my > non-scientific observations are that enabling all of the features that > are supported by a particular ethernet controller does not appear to > have any downsides (in terms of functionality, throughput, stability) > while appearing to have a beneficial impact on the interrupt rate. > > My question to you knowledgeable lot: does the use of offload features > of ethernet chips have a beneficial impact on system power consumption? > If so, should powertop be suggesting to turn these features on? >
Most offload features (TSO etc) end up helping (a little). Anything that makes the system more efficient will help; it's the "if you have less work to do you consume less power" concept. Exception tends to be TOE (total offloading), since TOE tends to be implemented by just another CPU, one on the card. This tends to be a loss in terms of power, because you now have 2 cpus slurping power, having just one tends to be more optimal. As for powertop suggesting this: I'm actually surprised these features arent on by default already. They should be.... If you have a specific one in mind, can you give some examples? It's easier to discuss such things on a specific case basis _______________________________________________ Power mailing list [email protected] http://www.bughost.org/mailman/listinfo/power
