Talk:Glossary

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additional terms for consideration

  • telepathy
See Telepathy --morgs 10:15, 9 June 2008 (EDT)
  • salut
See Telepathy Salut --morgs 10:15, 9 June 2008 (EDT)
  • mesh view as synonym for group view?
While mesh view is often used as a synonym for Neighborhood view, the other participants you see there are not necessarily accessed over the mesh network - instead, you may be using an Access Point and/or a Jabber server at the time. So you could explain "mesh view" as "Neighborhood view", but it's a weak association, one that I'd rather went away... --morgs 10:08, 9 June 2008 (EDT)
  • rpm / yum
  • suspend (semi-stub added to OS and firmware section) (User: Nicabod)
  • resume (ditto) (User: Nicabod) 03:22, 9 June 2K8

Cjl 22:50, 31 March 2008 (EDT)

Although I've been reading about Suspend and Resume for months, in Walter Bender's weeklies, where details of trying to improve its performance were detailed, I've never learned just what these terms mean precisely. Plainly, to suspend means, loosely, to set aside or put away, figuratively, to stop work with the intent of resuming it later. However:

When the XO is suspended, what suspends it? Timeout? User action (likely), but what kind? Button press? Selecting an icon or menu item? Closing up the machine? Command from the mesh (unlikely)? None, or several of those? Others? What does the user do to resume, or does a signal on the mesh do it (very unlikely to be the only way to resume), or both?

When suspended, what is the internal state of the XO? Low power, likely, but is the XO powered down except for the clock/calendar?

What happens to the OS when the XO is suspended? Does it go into standby -- what runlevels as it suspends? Resume must be the reversal, of course.

Are these questions mostly answered implicitly in online documentation? If so, where?

Nicabod

Suspend and resume. It's about power management - turning things off to prolong the battery. Specifically, suspend normally refers to turning the CPU off. Conventional laptops often have a "suspend to RAM" option, which saves the CPU state in RAM, but requires some (lower) amount of battery power to retain the contents of RAM, and "suspend to disk" or "hibernate" option which saves all the RAM contents to disk and then powers off completely. The XO-1 doesn't have enough storage space for suspend to disk, so suspend is always to RAM.
A clever thing the XO-1 can do is to power the CPU off while leaving the screen on (albeit "frozen"). This is used for ebook mode - when reading a PDF in Read, the CPU isn't needed at all until you press a key. Then it wakes up, displays the next screenful, and goes back to sleep.
The mesh network hardware also remains on when suspended, so that the XO-1 can forward mesh network traffic while suspended.
Suspend would be triggered by:
  • Idle (no user activity)
  • Pressing the Power button
  • Closing the lid
Resume would be triggered by:
  • Pressing a key, if it suspended on idle
  • Pressing the Power button again
  • Opening the lid
  • Receiving network traffic that needs to be acted on by the CPU (e.g. for collaborative activities you are in)
Suspend and resume is managed by ohm power manager.
Current problems with suspend and resume are:
  • Doesn't "wake on multicast" yet (although it will soon). This means activity collaboration breaks with it enabled.
  • Issues with SD cards not working after resume.
Disclaimer: some of the above may be inaccurate, but it's my understanding of the details...
--morgs 09:19, 9 June 2008 (EDT)

Thank you for the info.! I do wish it were published where it would be easier to find. Nicabod 14:22, 19 June 2008 (EDT)

Definition needed: Libertas (module) (probably Networking) Nicabod 14:22, 19 June 2008 (EDT)

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