The power-management-guide currently available on the Gentoo site was written a few years ago when no simplified methods or tools existed for handling power management. However, developments on laptop-mode-utilities as well as integrated advanced power management within the desktop environments should allow users to setup their laptop accordingly without going through this much trouble. The guide should therefor best be updated (or rewritten) to reflect these changes. Reproducible: Always
Extract from https://bugs.gentoo.org/show_bug.cgi?id=367145#c2 [reply] [-] Description Libor Polčák 2011-05-13 21:42:19 UTC I use battery runlevel as suggested in Power Management Guide (http://www.gentoo.org/doc/en/power-management-guide.xml). After updating to new baselayout my computer always boots into battery runlevel. The script /etc/acpi/actions/pmg_switch_runlevel.sh (copied from the guide) exits with: /etc/acpi/actions/pmg_switch_runlevel.sh: line 29: /var/lib/init.d/softlevel: File or directory does not exists I believe that the directory /var/lib/init.d/ is gone with new baselayout. However, neither the migration guide (http://www.gentoo.org/doc/en/openrc-migration.xml), nor the http://www.gentoo.org/doc/en/power-management-guide.xml says what replaces the directory. Reproducible: Always Steps to Reproduce: 1. Install Gentoo with baselayout1 2. Follow http://www.gentoo.org/doc/en/power-management-guide.xml 3. Follow http://www.gentoo.org/doc/en/openrc-migration.xml Actual Results: /etc/acpi/actions/pmg_switch_runlevel.sh does not find /var/lib/init.d and consequently allways enters battery runlevel Expected Results: /etc/acpi/actions/pmg_switch_runlevel.sh checks if the system indeed runs from battery and switch to battery level accordingly. [reply] [-] Comment 1 Josh Saddler 2011-05-13 23:57:48 UTC Baselayout/ACPI maintainers: can you guys tell the GDP what we need to do for this guide? [reply] [-] Comment 2 Duncan 2011-05-14 01:16:36 UTC [User with an Acer Aspire One netbook, here. I used the gentoo-wiki and other net resources to setup the netbook, but did NOT use Gentoo's Power Management Guide as I didn't end up needing it.] The Power Management Guide as it exists ATM is rather dated in general. Laptop-mode-tools (LMT) has evolved from its original purpose of controlling disk activity (only), to be a rather all encompassing set of tools (as the name suggests) for automated wall-power/battery-power migration. There are LMT modules for all sorts of stuff, to the point that once a user explores and sets up all the LMT modules relevant for his hardware, there's not a whole lot more to do, and the nice part of it is that all the modules have sane defaults, disabled or failing gracefully if the hardware or configuration doesn't support them, enabled with defaults that make sense for both laptop-mode (battery) and plugged-in-mode if the hardware and config is there to do so. Individual tweaks may be necessary for individual installations, but in general, the package fits in very well with Gentoo's "add the bootscript to the default runlevel and it just works as installed" policy. So I'd suggest a rewritten Power Management Guide centered around laptop-mode-tools. Of course in Gentoo, that still means getting all the kernel settings correct, for instance, so that part of the guide will still be there. Covering the basics of frequency-scaling, etc, is still useful, but I'd recommend doing it in the context of LMT, particularly since this guide is specifically aimed at laptop users (not server users or others interested in wall-power-only power-savings). Same with ACPI. Same with display dimming and power management. Of course LMT still covers disk management. There's even modules to control sound chips (some of them, more common in laptop/netbook chipsets, at least) and wifi vs ethernet, for instance, in current LMT, not really covered at all in the current guide. And perhaps the key bit. Once laptop-mode-tools is appropriately setup, there's now little need for a separate battery runlevel, so I'd suggest dropping that bit entirely, which gets it out of the hair of the openrc folks. It's certainly still possible some users may still want a battery runlevel, but really, no more so than individual installations might want customized runlevels for other usage, and the generic documentation should cover that, no need to do so in a laptop focused power management guide specifically. Bottom line, I'd be interested in (and am thus volunteering to) help(ing) with the rewrite. As I only really have experience with the one netbook (and given my usual verbosity) I'm not sure how effective I'd be at the initial writeup, tho if no one else is interested I might be persuaded to try that too, but I'd certainly be open to reviewing drafts created by others. Meanwhile, I'd suggest at least a (dated) simple note at the top of the existing guide, to the effect that it's a bit dated and hasn't been rewritten yet for baselayout2/openrc. "We're working on it." Perhaps with an address to contact for anyone interested in being CCed on further discussion, and/or a link to this bug. If there's an off-bug discussion list setup for this, please do CC me, or reply to the bug asking interested people to CC.
I'm working on a rewrite of the power management guide. Current draft is at http://dev.gentoo.org/~swift/docs/previews/power-management-guide.xml and gives initial focus on the laptop-mode-tools package. It the covers some more advanced tools (like cpufreqd for a more granular CPU frequency management approach). This rewrite does not work with an additional "battery" runlevel (no need for it imo) nor does it create additional scripts for users to manage (and for us to have bugs on when things change).
No updates otherwise on the document, except that I now add a link to a thinkwiki article that has an exhaustive list of measures one can take for powermanagement, and a link to the powertop package site. If okay, I'll commit this one over the older one.
Document committed to CVS.
