[PC-BSD Testing] 9.1-BETA1 now available!
VaNs9 at yandex.ru
Mon Jul 23 04:25:28 PDT 2012
While we are in BETAs and RCs, can we "turn on" deeper C-states?
I mean setting:
performance_cx_lowest="LOW" # Online CPU idle state
economy_cx_lowest="LOW" # Offline CPU idle state
in the rc.conf.
If it leads to troubles, we can exclude this setting from release. This settings may make system unresposive for a few seconds, _after_ the system was idle. I've expected such unresponsiveness with apci_throttle enabled (that's the default in stock FreeBSD) and super power-efficient Intel Atom (Z520), which is able to enter really deep C-states. It seemed to be a combo of (by default enabled) apci_throttle, powerd and _cx_lowest settings which made "lags". So while we have acpi_throttle disabled by default, imho, we can try enabling this C-states.
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