[Kolab-devel] Re: Progress reports

[Martin Konold]

Am Mittwoch, 7. Juli 2004 16:27 schrieb Stuart K. Bingë:

Hi,

> On Tuesday, 06 July 2004 21:17, Martin Konold wrote:
> > > Due to the fact that the PHP IMAP extension (which is based on the UW
> > > c-client library) is not able to handle annotations, we've had to go
> > > around it by using the Net_IMAP package from PEAR, which implements the
> > > IMAP protocol in pure PHP.
> >
> > What are the performance implications of Net_IMAP instead of client?
>
> I haven't done any performance comparisons just yet. If the performance of
> Net_IMAP is abysmal (which so far does not seem to be the case) we can
> always restrict its use to the small (in comparison to the rest of the IMAP
> usage) number of cases where we need ANNOTATEMORE support.

I looked deeper into the performance problems of the server side freebusy 
generation (tested with 10.000 events in a folder). The current 
implementation is _extremly_ slow so that fb generation takes more than 5 
minutes on an otherwise idling 3.3 GHz machine.....

> > Did you consider to extend the client library? (Yes, I know it is _old_
> > c-code.)
>
> I did consider that. For about five minutes. I essentially came to the
> conclusion that there is no way in hell I am going to touch that code. If
> one were to extend the c-client library, it would still take *WAY* too long
> to actually trickle down into the PHP IMAP extension. With Net_IMAP we
> already have the solution available to us.

No this is no solution. I checked and will send a patch to this list later 
this week offering a patch to the c-client library so that we will get 
_extreme_ performance gains. (about two order of magnitude!)

In addition I took some time to look into the long proposed chaching of 
<IMAP-UID,ICAL-UID> and <ICAL-UID,list of FB tuples).

This can according to the tests speed up the generation of fb lists by more 
than a factor of 100.

The very same optimisations apply also for the horde based webclient!

Regards,
-- martin

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