On Sunday, 24 June 2007 02:28, Alan Stern wrote: > On Sun, 24 Jun 2007, Rafael J. Wysocki wrote: > > > > Is this design okay with system states in which the CPU is able to run? > > > > Do you mean the patch or the suggestions above? > > The suggestions. > > > > Right now the states we have are On, Standby, and Suspend, and the CPU > > > runs only in the On state. But on some platforms there could be > > > multiple states in which the CPU is able to run, albeit with degraded > > > performance. > > > > I wouldn't call those system sleep states. For example, ACPI defines system > > sleep states as the states in which no instructions are executed by any CPUs > > and I think that's reasonable. > > > > Moreover, the ACPI spec insists that transitions between different sleep > > states should be made through the On state. > > Okay. But on non-ACPI systems, do we want to restrict the > /sys/power/state interface to sleep states? How then should the user > tell the system to go to a low-performance run state? Or should that > be handled automatically within the kernel? I think that the /sys/power/state interface should be restricted to system sleep states only and we should introduce another one for handling non-sleep low-power states. IMHO, the kernel can automatically transition to non-sleep low-power states, but the users should be able to define the conditions for that. Also, the user should be able to force the transition if necessary/desired. Greetings, Rafael -- "Premature optimization is the root of all evil." - Donald Knuth _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
