[KPhotoAlbum] Startup performance: the final frontier

[Andreas Schleth]

Am 31.05.2017 um 04:22 schrieb Robert Krawitz:
> The last big performance problem I have with kpa is
...

Hi Robert,

I have been following your exchanges with Johannes about the performance 
problems of KPA for a while and would like to add my two cents (or is it 
five?).

First, changing the structure of the index.xml at this point would be a 
really bad move from my point of view.  Why?

I still use a canned version KPA 4.1.whatever with an ancient Suse 11.2 
in a virtual machine if I have to time shift some images from a foreign 
source. And from there I work directly on my original database via 
host-only network.  In that old KPA version (KDE4) the kipi-plugin for 
time shifting still works. In the current version it is out of business 
because some design decisions of the digicam community.  AFAIK Martin 
Füssel is looking into this, but this might take a while.

The charming thing about KPA at the moment is, that my database 
operations with this ancient KPA version on index.xml files (maintained 
normally with the most recent git master) do not corrupt the database.
Thus, this is a feature (backward compatibility), that would be lovely 
to keep for the time being.
[[I probably only understood some 10% of what you wrote about, but 
seeing mentions of xml structure and parsing made me listen up ...]]

Second, as you are looking at performance ... did you perchance ever 
look at thumbnail generation?  My database of some 30000 images resides 
on a NFS share and rebuilding thumbnails still takes close to 30 minutes 
with KPA not being very reactive in the meantime, even tending to crash 
in the (longish) interval until the progress bar first shows up - this 
is after Johannes did some improvements to the process already.  So, 
this would be a point where you could harvest many minutes and not 
seconds of performance gain :-)  [[Also the files in the .thumbnails 
folder always have the wrong (for my setup) permissions (rw-r--r-- while 
everything else is rw-rw-r--) - but this might be a problem existing 
between keyboard and (my) chair]]

Anyway, it is great to see an MIT engineer hacking away at KPA.

Best regards, Andreas