[Korganizer-devel] [Bug 133614] add caldav support for sharing calendars

[Kumaran Santhanam]

https://bugs.kde.org/show_bug.cgi?id=133614





--- Comment #69 from Kumaran Santhanam <kumaran alumni stanford org>  2011-01-22 20:45:46 ---
Hi Grégory,

Thank you for the quick and detailed response.

> Are you talking about the resource performance here? If that's the case the 
> only place where there is a "problem" is with the initial sync of calendars 
> that contain a lot of entries, as all will be downloaded from the server. 
> There is room here for some improvement, for example by fetching first the 
> items that are around the current date, but there are some more features I'd 
> like to see before starting this kind of optimizations. Besides this both 
> resources should be on par.

There is probably a mix of resource and KOrganizer issues.  However, I do think
that as a baseline improvement, the resource should not cache the entire
calendar.  We came across this some time back during KCalDAV development. 
Currently, we have DAViCal server with nearly a dozen calendars and thousands
of simple and complex events.  Caching the entire calendar presents the
following problems:

1) Very slow performance over remote VPN links.

2) Extra server overhead for NFS-mounted home directories.

3) Security concerns in the case of a lost or stolen laptop.

For these reasons, KCalDAV is set to cache events +/- 90 days from the current
date.  This is a constant that can be tuned, but we have found that this value
works pretty well for most situations.  Time-limited caching also has the
desirable effect of preventing calendar lookups from becoming O(n) with respect
to the size of the calendar.