Batch Queue Manager and database lock.

[Maik Qualmann]

Gilles,

please test the behavior of digiKam after my last commits.

Maik

Am Samstag, 12. August 2017, 19:33:10 CEST schrieb Maik Qualmann:
> I can reproduce the problem. I look for the cause.
> 
> Maik
> 
> Am Samstag, 12. August 2017, 17:53:52 CEST schrieb Gilles Caulier:
> > Hi all,
> > 
> > I remember some fixes done in more and less recent version about BQM
> > about database lock, especially from Maik.
> > 
> > While this summer i take a lots of panorama in French Alps. I use
> > typically BQM in background to adjust the colors of target files (JPG)
> > using a dedicated BQM workflow :
> > 
> > 1/ Local Contrast to render image as pseudo HDR (the photo is more
> > luminous). 2/ WB tool to increase the saturation.
> > 
> > For ex : https://goo.gl/photos/FVisJdYHd4i8mZzF9
> > 
> > 
> > Processing Pano files of 200Mpx in BQM take age. I don't use
> > multi-core because my laptop has just 4 cores (i5). I want to use
> > another one to perform triage, or use editor, or run Panorama tool.
> > 
> > And the problem appear. While BQM tool is running, navigating in album
> > contents give empty views. No item are visible. When BQM is done, all
> > re-appear. It's always reproducible.
> > 
> > I don't suspect a database lock, but something wrong with the
> > ActionThreadBase instance from BQM which reserve all cores and block
> > database interface which use also ActionThreadBase interface.
> > 
> > Typically, i think that set max cpu core to use with QThreadPool
> > (inside ActionThreadBase) is something static. One QThreadPool is
> > certainly a singleton in Qt and changing the number of threads in one
> > instance of ActionThreadBase change the behavior for all
> > ActionThreadBase instance.
> > 
> > What do you think about ? Can somebody can confirm the problem ?