Salut and Suspend/Resume issues

[Ricardo Carrano]

I believe the most important issue here is that, the way it is now,
suspend/resume will make a disconnected mesh unusable.


On Feb 17, 2008 4:11 AM, Giannis Galanis <galanis at laptop.org> wrote:

> There are a couple of important issues/bugs regarding Salut and
> Suspend/Resume.
>
> FIRST, there is a "sugar issue", (or at least it seems so).
> When an XO resumes after long suspends, all icons(APs, XOs, but not the
> meshes) instantly vanish*(#6467)*. Then they slowly reappear. Although
> with the APs the situation is pretty straightforward, with the XOs we have
> several cases:
>
>    - all XOs in the mesh return almost instantly
>    - all or some XOs return slowly one by one
>    - nothing returns, and avahi peer list is empty*(#6498)*
>
> It seems that although suspend should keep the previous situation frozen,
> in fact the avahi peer list is affected.
>
>
> SECOND, we have a network issue, which suggests a "war" between
> suspend/resume and avahi/salut
> Suspend will be interrupted only with unicast packets, but Salut/avahi
> rely on multicast packets.
>
> The result is that  when an XO that appears in the mesh view is suspended,
> avahi will treat it just as if it has left the mesh.
>
>
>    - When an XO is being used(not suspended), all other suspended XOs
>    in the mesh will start failing 1 by 1
>    - From the moment an XO is suspended in about 10-30min the icon will
>    vanish.*(#6282)*
>    - If within this time new XOs join the mesh than the icon will
>    vanish instantly!!*(#5501)*
>    - If gradually several removed XOs start to resume, their icons will
>    start returning
>
> *****As you can see, the XOs have very little chance to even see each
> other******
>
> RESULT:
> A mesh of several XOs will avoid icons flashing here and there, ONLY if no
> XO has been idle for more 10min, which is rather unlikely.
>
> Considering the effects of the FIRST issue, you would practically have to
> restart sugar or switch channel back and forth to return to your original
> status.
>
> Salut/avahi are very sluggish in handling failed connections, and suspend
> resume enhaces this effect.
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.laptop.org/pipermail/devel/attachments/20080219/bd9ab8c0/attachment.html>