#4824 HIGH Update.: Should shutdown gracefully on low battery

[Zarro Boogs per Child]

#4824: Should shutdown gracefully on low battery
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  Reporter:  cjb                  |       Owner:  cjb     
      Type:  enhancement          |      Status:  new     
  Priority:  high                 |   Milestone:  Update.1
 Component:  power manager (OHM)  |     Version:          
Resolution:                       |    Keywords:  power   
  Verified:  0                    |  
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Comment(by gnu):

 18% sounds way too high to kick off the user and force a shutdown.  I can
 recall many times fighting with DOS laptops that tried to kick me off just
 as I was racing to finish something before the battery *actually* ran out.

 If the laptop is idle, it should be suspending and the battery shouldn't
 be dropping much.  (Ohm could wake up from idle when it hits 2%, and do a
 clean shutdown.)  If the laptop isn't idle, please don't suddenly shut it
 down out from under the user!

 One thing we'll need to have clear is what the "N%" actually measures.  I
 thought the EC was preventing us from even seeing the top 10% and bottom
 10% of the battery capacity.  (At least on NiMH; maybe or maybe not on
 LiFePO.)  The EC will force a hard shutdown at real-10% (or maybe 0% for
 LiFePO)?  Question is whether the kernel-readable N% includes that 10%
 margin -- or not.  I argue the kernel should not report unavailable
 capacity; and that Ohm therefore should not assume a 10% offset from what
 the kernel is reporting.  (Particularly if it differs based on battery
 types; we want that info centralized in the EC and not spread around the
 EC, kernel, and ohm.)

 If suspend was smart, it would do a sync() sometime before or during a
 long-term suspend; in case the power never comes back, the filesystem at
 least would be in sync.

 Activities should definitely be listening to dbus for global signals --
 like "Out of memory, free some up!" as well as "sync your stuff up 'cause
 we're suspending for a long time" and "shutting down".

-- 
Ticket URL: <http://dev.laptop.org/ticket/4824#comment:4>
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