[KPhotoAlbum] Building Thumbnails is partially broken

[Andreas Schleth]

Hi (Tobias, I think),

with the most recent build (*-20-*) I encounter some instabilities with 
building thumbnails:

It all started, when 5 new images would not show thumbnails in the 
viewer - no idea how to persuade KPA to display something. Permissions 
on the images are OK and tagging (with preview) is OK.

OK, I have some spare time and hit: "Maintenance - build thumbnails" ...

When you touch absolutely nothing in KPA while it is building (20000 
images ...) the files accumulate in .thumbnails and the rebuild process 
seems to succeed (it is on its 4th try and not finished yet while I 
write this).

If you try to do any navigation in KPA, at first it is not responsive at 
all - seems to be frozen.  Then, after a while, it seems to work again 
(displays - finally - a working status bar). However, when selecting a 
random year (where thumbnails have not yet been built) KPA dies after 
the thumbnail view has produced the first (very) few thumbs.  The 
thumb-x files have stopped growing and KPA is catatonic.

So, the current process to (re-)build the thumbs seems to be a bit too 
fragile for general consumption.

Cheers, Andreas