At Tue, 20 Nov 2012 09:56:19 +0100, David Henningsson wrote:
On 11/20/2012 09:32 AM, Takashi Iwai wrote:
At Tue, 20 Nov 2012 09:07:21 +0100, David Henningsson wrote:
It does put another question - from where does powertop get its values, and do we have to do anything on our side to make sure / aid them being correct?
powertop checks /sys/class/sound/hwC*D*/power_{off|on}_acct files. They contain the time (in ms) how long the codec is in the power-save mode.
Thanks. But I have also recently seen a computer where powertop showed a Watt number, essentially saying that the codec consumed 1.4 Watts or so (I don't remember the exact number). Have you seen that too?
When 1.4W is constantly consumed even without PCM, it's a bit too high. But with PCM playback, about 1W usage can be measured normally, I guess.
Takashi