#6884 HIGH 8.2.0 (: Incorrect number of laptops shown in neighborhood view

[Zarro Boogs per Child]

#6884: Incorrect number of laptops shown in neighborhood view
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   Reporter:  wad               |       Owner:  Collabora           
       Type:  defect            |      Status:  new                 
   Priority:  high              |   Milestone:  8.2.0 (was Update.2)
  Component:  presence-service  |     Version:                      
 Resolution:                    |    Keywords:                      
Next_action:  diagnose          |    Verified:  1                   
  Blockedby:                    |    Blocking:                      
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Comment(by robot101):

 This bug seems veeeeeeeeeery familiar. We had it very early on during our
 development cycle when we used the @all@ shared roster group, meaning
 every single registered user on the server. The reason was an interaction
 between in-band registration, and shared rosters. Each client thread
 inside ejabberd filled their roster with a /copy/ of all the registered
 users when they connected, but didn't get this list updated when new
 people registered on the server. So even though the newly-registered user
 had the currently signed-on people on their list, the client thread of the
 existing user doesn't think the new user is eligible to see the current
 user's presence, because they're not on their old copy of the list, so
 doesn't reply to the presence probe. The new user therefore saw all
 currently-connected users as offline, until the currently connected users
 signed out and in again. The fix was a little hack from one of the
 ejabberd guys to push out a new roster item to all applicable shared
 roster group members when a new user was registered.

 For the @online@ group, a similar failure would be if the people who just
 signed on weren't being correctly pushed onto the rosters of the already
 signed-on people. This means each person would see everyone who signed
 onto the server before them, but nobody who signed on after them. It's
 some time since I worked on it, but in my (inefficient) implementation of
 @online@, I definitely hooked the "newly connected user" and did some very
 crude production and updating of every other person's roster item for the
 newly connected user. It's possible that the Process One optimisations
 introduced a regression in this area.

 Or perhaps it only applies in a corner-case, where a newly-registered
 person does appear for currently-signed on users, but an existing
 registration who signs back in does not. Can I get a full list of the
 patches that're applied on the servers which exhibit this issue?

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Ticket URL: <http://dev.laptop.org/ticket/6884#comment:12>
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