Bug 107030
| Summary: | release notes ACPI discussion incorrect / unclear | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Chris Ricker <chris.ricker> |
| Component: | distribution | Assignee: | Ed Bailey <ed> |
| Status: | CLOSED NEXTRELEASE | QA Contact: | Bill Nottingham <notting> |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | rawhide | CC: | barryn, davej, notting, rvokal, tammy.c.fox |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2003-10-19 12:03:41 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
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Description
Chris Ricker
2003-10-14 14:57:15 UTC
Power consumption is done by the base modules some. Sleep/suspend is almost certainly guaranteed *not* to work, AFAIK. Dave - comments? I requested the extra Fedora bugzilla components a while back. I'll check into it and make sure they are added. With acpi=on, /lib/modules/$(uname -r)/kernel/drivers/acpi/* gets loaded, and you get some of the basic power management stuff. The original statement in the release notes, OTOH, suggested to me that I'd still have to recompile even to get very basic power management things like battery state reporting (as was the case in RHL 9), and that's not true.... Along the same lines, the fedora core kernel appears to have support for the cpu throttling stuff (speedstep / powernow / longhaul / whatever other marketing term). With acpi=on, my mobile athlon says powernow: AMD K7 CPU detected. powernow: PowerNOW! Technology present. Can scale: frequency and voltage. ... powernow: Minimum speed 1064 MHz. Maximum speed 1795 MHz. On the 2.6 kernels, there are nobs in sysfs for controlling this from userspace. If there are equivalents for the 2.4 port (and there may not be -- I haven't found any, and don't see much in the code to suggest there should be), mentioning them in this section of the release notes would also be helpful The powernow etc stuff is from cpufreq, nothing to do with ACPI at all. You can control it with /proc/cpufreq The docs are in the kernel packages Documentation/cpu-freq/ directory. You're right that cpufreq isn't ACPI, but it is power-management related. The current docs for it say nothing applicable about how to actually use it. If you actually read through them, you'll find that they only provide reference for the 2.6 (sysfs) commands. For the old interfaces -- /proc/cpuinfo (which does work with the Fedora kernel) and /proc/sys/cpu/* (which doesn't work, except as a read-only info source, with the Fedora kernel) -- they only say: "Depending on your kernel configuration, you might find the following cpufreq-related files: /proc/cpufreq /proc/sys/cpu/*/speed /proc/sys/cpu/*/speed-min /proc/sys/cpu/*/speed-max These are files for deprecated interfaces to cpufreq, which offer far less functionality. Because of this, these interfaces aren't described here." Since this is a new feature in the Fedora kernel, and since the in-kernel documentation is incomplete / unusable, it'd be nice if the release notes added a paragraph covering echoing values to /proc/cpufreq to select rates, since at least that part works even if there aren't true equivalents to all the sysfs nobs.... The overall problem here with the release notes is that the current wording regarding ACPI makes people think that the situation for those of us with newish laptops is what it was with RHL 9 -- that you had to roll your own kernel with ACPI support just to use the machine. The reality is different from that -- between acpi=on and cpufreq, I can actually get over 2 hours out of a single battery on some of my AMD laptops and can functionally work while keeping an eye on battery state, knowing when to shutdown, etc., with the stock kernel. Ok, I've updated the entry on acpi, and have added a new entry describing /proc/cpufreq. You'll see these updates reflected in the next release in early November. Thanks for your feedback! |