SUMMARY STEPS TO REPRODUCE 1. open a 'large' pdf with images (it is easier to see it) like that one: https://www.dropbox.com/s/qcxcbyyppg8p2ui/DRAGONS-GuideDuJoueur.pdf?dl=0 2. Read the document OBSERVED RESULT It is slow to draw a page. It took seconds to do it and it is increasing little by little and the CPU usage is going through the rough. I remove every option I can to improve the performance but nothing change. I tried with evince and the problem is not there. EXPECTED RESULT Smooth reading of pdf file. SOFTWARE/OS VERSIONS Linux/KDE Plasma: (available in About System) Arch Linux KDE Plasma Version: 5.18.3 KDE Frameworks Version: 5.68.0 Qt Version: 5.14.1 ADDITIONAL INFORMATION Processor: 12 x intel Core I7-8750H Memory: 15,2 GiB of RAM
Okular doesn't do any PDF rendering by itself. If PDF rendering is slow please open a bug at poppler issue tracker https://gitlab.freedesktop.org/poppler/poppler/issues/new?issue
As I mention it does not happen with evince so it coule be poppler but the qt specific part. I will be surprised that I am the only one affected but I have a workaround (using evince).
Quick testing (Core 2 Duo E4700, SSD Kigston A400, 6GB of RAM). Fit page to width, time to load 14th page from the first page, cold start. Poppler-based viewers: Okular 1.10.70 (poppler 0.86.1) - 10 secs Evince 3.32.1 - 5 secs qpdfview 0.4.18beta - 10 secs Non-popler-based: MuPDF 1.16.1 - 1 sec FoxIt Reader for Linux 2.4.4.0991 - 1 sec
Issue open on poppler as asked. I cannot see why this bug has been closed with 'resolved upstream'. Perhaps it is true but without more information on the commit or solved issue on poppler it is difficult to be sure that the problem will not be forgotten and that will be a shame. Okular used to be the best pdf reader on linux and going to evince is kind of going backwards but the rendering problem is killing okular (I am pretty sure that most of the okular usage is to open pdf file). https://gitlab.freedesktop.org/poppler/poppler/-/issues/899