[Okular-devel] Epub qtextdocument high cpu usage

[Albert Astals Cid]

El Dimarts, 18 de juny de 2013, a les 01:39:30, Jaydeep Solanki va escriure:
> On Mon, Jun 17, 2013 at 11:31 PM, Albert Astals Cid <aacid at kde.org> wrote:
> > El Dilluns, 17 de juny de 2013, a les 21:42:23, Jaydeep Solanki va
> > 
> > escriure:
> > > On Sun, Jun 16, 2013 at 8:42 PM, Albert Astals Cid <aacid at kde.org>
> > 
> > wrote:
> > > > El Diumenge, 16 de juny de 2013, a les 20:29:37, Jaydeep Solanki va
> > > > 
> > > > escriure:
> > > > > Hello,
> > > > > As I was finding it difficult to make progress using webkit to
> > > > > render
> > > > 
> > > > epub,
> > > > 
> > > > > I spent some time experimenting around with QTextDocument.
> > > > > A small patch is attached which fixes the issues with the body tag
> > 
> > (eg :
> > > > > background color).
> > > > > 
> > > > > It works fine with me, the only issue I'm facing is that it gives a
> > 
> > high
> > 
> > > > > cpu usage, which leads to lag while scrolling fast.
> > > > > 
> > > > > I'm not getting the reason behind its high cpu usage.
> > > > 
> > > > Have you tried running it with callgrind option of valgrind +
> > 
> > kcachegrind?
> > 
> > > Till now I didn't know anything about profiling, I'm glad you brought it
> > 
> > up.
> > 
> > > I looked at the stats,
> > > 
> > >    - 'okularGenerator_epub.so' collectively costs only 0.01 (self),
> > 
> > that's
> > 
> > >    also while loading the document.
> > >    - impact of QTextDocument in 'libQtGui.so' is around 0.03 (self)
> > >    - 'libokularcore.so' which contains TextDocumentUtils collectively
> > 
> > costs
> > 
> > >    0.68
> > > 
> > > It doesn't appear to have a major impact.
> > 
> > When you say high cpu usage you mean that top gives you high numbers? Or
> > you
> > are saying high cpu usage because it lags?
> 
> When scrolling quickly, the core on which Okular is running hits 100% usage
> (stats obtained using System Monitor).
> + it lags.

And it doesn't happen without your changes?

If not, start adding things one by one until you find out where the problem 
is.

Cheers,
  Albert

> 
> > Cheers,
> > 
> >   Albert
> >   
> > > > Cheers,
> > > > 
> > > >   Albert
> > > >   
> > > > > If you want me to create a review request, I'll do it.
> > > > > 
> > > > > Cheers,
> > > > > Jaydeep
> > > > 
> > > > _______________________________________________
> > > > Okular-devel mailing list
> > > > Okular-devel at kde.org
> > > > https://mail.kde.org/mailman/listinfo/okular-devel
> > 
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