[Tickets #12175] Re: ActiveSync misses changes from history database

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Ticket URL: http://bugs.horde.org/ticket/12175
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  Ticket             | 12175
  Updated By         | Michael Rubinsky <mrubinsk at horde.org>
  Summary            | ActiveSync misses changes from history database
  Queue              | Synchronization
  Version            | Git master
  Type               | Bug
  State              | Assigned
  Priority           | 1. Low
  Milestone          |
  Patch              |
  Owners             | Michael Rubinsky
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Michael Rubinsky <mrubinsk at horde.org> (2013-04-11 16:25) wrote:

>> This will miss changes again if the server is too slow (think about a
>> low end server swapping for a few minutes). The "endTS - fudge
>> factor" approach is safe.
>
> True. Sounds like a plan :)

Actually, thinking about this a bit more,  won't either approach be  
subject to the same issue from a slow/swapping server?

Regardless of which code adjusts the timestamp, there is still the  
chance that the query will run before the data is available in history.

E.g., history writes a bunch of entries at 12345, but due to swapping,  
it's not actually available in the history backend until 12350. In the  
meantime, at 12347 the activesync code is querying for changes (so it  
is asking up until lets say 12346). The changes will still never be  
picked up because the next activesync query will have ts_from of 12346.