JauntySuspendResumeHibernate

Revision 9 as of 2008-11-28 13:47:19

Clear message

Summary

Jaunty should be using just one method of Suspend/Resume/Hibernate and sticking to this one method. Jaunty needs to improve the overall Suspend/Resume/Hibernate experience with the help of suitable debug tools to fix buggy suspend/resume/hibernate issues.

Release Note

Rationale

There needs to be some rationalisation in the way suspend/resume/hibernate is controlled from userspace as there are several existing methods available:

  • Writing directly to /sys/power/state (lowest level)
  • Using /etc/acpi/sleep.sh (acpi-support)
  • pm-utils - current solution (as used by hal)

  • DeviceKit-power which supersedes the power-management functionality of hal and replaces pm-utils.

The acpi-support method of suspend/resume should be removed as it is legacy and should be transitioned into hal-info and pm-utils. Having this method as well as pm-utils seems unjustifiable - it's a different suspend/resume mechanism to pm-utils and duplication of different suspend/resume functionality is not helpful.

Either we continue with pm-utils or move to DeviceKit-power (which is supported by the new gnome-power-manager for GNOME 2.26). Depending on the choice, we should just have one solution for suspend/resume/hibernate instead of many.

Diagnosing and hence fixing broken suspend/resume/hibernate needs to easier. A Community based Wiki tutorial or troubleshooting guide (such as http://people.freedesktop.org/~hughsient/quirk/quirk-suspend-debug.html) needs to be written as the de-facto reference page to help users to gather information that can help pinpoint and fix problems. Also having a program/script that can test for known quirks and suggest pm-suspend workarounds could be helpful.

Debugging suspend/resume/hibernate issues can be notoriously difficult; being able do dump kernel messages early to a serial console is useful, however modern PCs do not have legacy serial port hardware, so providing a USB serial console driver in initramfs is required.

Use Cases

  • A user cannot get his laptop to resume. They visit the trouble shooting guide which lists known hardware issues and pm-suspend workarounds that they can try.
  • As above, but the user is informed they can run a quirk checking program which can automatically suggest pm-suspend workarounds.
  • A user cannot resume because they have problems with specific buggy drivers. The tutorial explains how to turn on the/sys/power/pm_trace "resume-trace" debugging procedure for finding buggy drivers to gather sufficient information to pin-point the relevant driver.
  • A user cannot hibernate their laptop. The tutorial explains how to make the hibernation core run in a test mode and then run through the 5 different test modes.
  • A user wants to attach an early kernel log message to a bug report. By plugging in a USB-serial dongle and enabling the USB serial console driver they can then capture the log on hardware which does no have a legacy serial port. The tutorial should explain how to enable the driver using kernel boot line options, e.g. add the following to the kernel boot command line: 

console=ttyUSB0,9600

Assumptions

Design

Implementation

pm-utils Quirk Checking Scripts

The Quirk checking script http://people.freedesktop.org/~hughsient/quirk/quirk-checker.sh perhaps could be included into the disto to help users pin-point suspend/resume quirks.

Initramfs Changes

To facilitate the debug via USB Serial console, the USB serial console kernel driver needs to be included into initramfs.

Migration

Deprecating /etc/acpi/sleep.sh (et al) requires release note documentation at a minimum and perhaps modifications to the acpi-scripts informing the user that these are now deprecated and should not be used.

Test/Demo Plan

Unresolved issues

BoF agenda and discussion

References

CategorySpec