[Okular-devel] [okular] [Bug 350798] New: Okular opens large PDFs very slowly

[Ruslan Kabatsayev]

https://bugs.kde.org/show_bug.cgi?id=350798

Bug ID: 350798
Summary: Okular opens large PDFs very slowly
Product: okular
Version: 0.19.3
Platform: Other
OS: Linux
Status: UNCONFIRMED
Severity: normal
Priority: NOR
Component: PDF backend
Assignee: okular-***@kde.org
Reporter: ***@gmail.com

Try e.g. this document: http://tinyurl.com/p3su6cp . (It's Intel's System
Programming Guide). It opens in about 25 seconds on my machine with Okular. For
comparison, Adobe Reader 9.5.1 opens this same document nearly instantly — less
than in one second!

Reproducible: Always

Steps to Reproduce:
1. Download the example document linked above
2. Try opening it with Okular
3. Wait until it shows the first page
4. (optional) Try the same in Adobe Reader and see how amazingly fast it shows
the document

Actual Results:
First page showed after ~25 seconds waiting for seemingly hung Okular

Expected Results:
The document should open nearly instantly, as is the case with Adobe Reader.

This was checked on Kubuntu 12.04 with its stock KDE and Kubuntu 14.04 with its
stock KDE version. User experience is the same.

[Burkhard Lueck]

https://bugs.kde.org/show_bug.cgi?id=350798

Burkhard Lueck <***@hube-lueck.de> changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |***@hube-lueck.de

--- Comment #1 from Burkhard Lueck <***@hube-lueck.de> ---
Kubuntu 14.10 utopic
$ okular --version
Qt: 4.8.6
KDE: 4.14.2
Okular: 0.20.2
libpoppler-qt4-4:
Installiert: 0.26.5-0ubuntu2

~ 3 or 4 seconds to display the downloaded pdf (9 MB)

[Albert Astals Cid]

https://bugs.kde.org/show_bug.cgi?id=350798

Albert Astals Cid <***@kde.org> changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |***@kde.org
Status|UNCONFIRMED |NEEDSINFO
Resolution|--- |WAITINGFORINFO

--- Comment #2 from Albert Astals Cid <***@kde.org> ---
Which poppler version are you using?

[Ruslan Kabatsayev]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #3 from Ruslan Kabatsayev <***@gmail.com> ---
0.24.5-2ubuntu4 on Kubuntu 14.04
0.18.4-1ubuntu3.1 on Kubuntu 12.04
0.33.0 on LFS

All they show qualitatively the same problem.

[Albert Astals Cid]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #4 from Albert Astals Cid <***@kde.org> ---
Do you have a remote printer that is unplugged?

[Ruslan Kabatsayev]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #5 from Ruslan Kabatsayev <***@gmail.com> ---
All remote printers I have are plugged in. But the problem also reproduces with
network down.

[Albert Astals Cid]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #6 from Albert Astals Cid <***@kde.org> ---
Is okular using 100% of your CPU? Or just sitting there doing nothing?

[Ruslan Kabatsayev]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #7 from Ruslan Kabatsayev <***@gmail.com> ---
Uses 100% of a single core (i.e. 25% total on a quad-core machine).

[Ruslan Kabatsayev]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #8 from Ruslan Kabatsayev <***@gmail.com> ---
Just tried running sysprof with it, it appears to take most of the time in
DecryptStream::lookChar(). On the machine I'm now, with Kubuntu 14.04, it takes
4-5 seconds to open the file, within which sysprof did the sampling.

[Albert Astals Cid]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #9 from Albert Astals Cid <***@kde.org> ---
I'm confused now, you're saying that it takes 5 seconds or 25?

[Ruslan Kabatsayev]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #10 from Ruslan Kabatsayev <***@gmail.com> ---
On one machine (LFS with poppler 0.33.0) it takes 25 seconds, on this one
(Kubuntu 14.04 with poppler 0.24.5) it's 5.

[Albert Astals Cid]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #11 from Albert Astals Cid <***@kde.org> ---
Did you do the sysprof sampling in that machine that is fast? Why?

[Ruslan Kabatsayev]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #12 from Ruslan Kabatsayev <***@gmail.com> ---
Yes, I did it on the fast one, because it's near me. I'll get to the other one
after several hours. Should I try profiling there too?

[Albert Astals Cid]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #13 from Albert Astals Cid <***@kde.org> ---
Yes, i'm not interested in profiling on a computer where there's nothing to
fix.

[Ruslan Kabatsayev]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #14 from Ruslan Kabatsayev <***@gmail.com> ---
So you consider 5 seconds vs almost instant as in Adobe Reader a negligible
difference?

[Albert Astals Cid]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #15 from Albert Astals Cid <***@kde.org> ---
Do you consider 25 seconds vs 5 seconds a negligible difference?

[Ruslan Kabatsayev]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #16 from Ruslan Kabatsayev <***@gmail.com> ---
Created attachment 93820
--> https://bugs.kde.org/attachment.cgi?id=93820&action=edit
Sysprof log

OK, now I got to this machine with 25 seconds opening. Here the log is more
verbose due to better-installed debug symbols or whatever (and it doesn't
contradict my observations on the faster machine). I attach the syslog saved
log.

[Albert Astals Cid]

https://bugs.kde.org/show_bug.cgi?id=350798

Albert Astals Cid <***@kde.org> changed:

What |Removed |Added
----------------------------------------------------------------------------
Status|NEEDSINFO |UNCONFIRMED
Resolution|WAITINGFORINFO |---

--- Comment #17 from Albert Astals Cid <***@kde.org> ---
The big slowliness has been fixed by the newer poppler release as we can see.

I can't see any huge difference between the time Adobe takes to open the file
and the time Okular takes to open the file in my system.

We can leave this open in case you feel the difference is bad but i wouldn't
hold my breath on getting someone to look at it. Maybe you can? You seem to
know a bit about technical stuff.

[Ruslan Kabatsayev]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #18 from Ruslan Kabatsayev <***@gmail.com> ---
If I'm not mistaken, 0.33 should be newer than 0.24. Am I wrong?

[Ruslan Kabatsayev]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #19 from Ruslan Kabatsayev <***@gmail.com> ---
@Albert
What time does it take for Okular to open the file on your system? And what OS,
poppler and Okular versions are you using? I can't seem to figure out in which
version of what it should work without slowdowns. All systems I tried appeared
too slow to me (5 seconds is also slow, since even MuPDF opens it instantly,
even on the machine with Okular's 25 seconds.)

[Albert Astals Cid]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #20 from Albert Astals Cid <***@kde.org> ---
(In reply to Ruslan Kabatsayev from comment #18)

Post by Ruslan Kabatsayev
If I'm not mistaken, 0.33 should be newer than 0.24. Am I wrong?

No, you're correct.


(In reply to Ruslan Kabatsayev from comment #19)

Post by Ruslan Kabatsayev
@Albert
What time does it take for Okular to open the file on your system? And what
OS, poppler and Okular versions are you using? I can't seem to figure out in
which version of what it should work without slowdowns. All systems I tried
appeared too slow to me (5 seconds is also slow, since even MuPDF opens it
instantly, even on the machine with Okular's 25 seconds.)

4 seconds. poppler 0.35 Okular 0.22.90

mupdf opens it instantly because it basically does "nothing"

poppler/qt4/tests/test-poppler-qt4 also opens it in 86 milisseconds, but
showing the big table of contents, etc is costly.

I'd say there's something wrong in your LFS build.

[Greg Lepore via KDE Bugzilla]

https://bugs.kde.org/show_bug.cgi?id=350798

Greg Lepore <***@rhobard.com> changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |***@rhobard.com

[Blase Johnson]

https://bugs.kde.org/show_bug.cgi?id=350798

Blase Johnson <***@outlook.com> changed:

What |Removed |Added
----------------------------------------------------------------------------
Resolution|--- |WAITINGFORINFO
CC| |***@outlook.com
Status|REPORTED |NEEDSINFO

--- Comment #21 from Blase Johnson <***@outlook.com> ---
Does it still take you a long time to open the document with a more recent
version of Okular?

[Blase Johnson]

https://bugs.kde.org/show_bug.cgi?id=350798

Blase Johnson <***@outlook.com> changed:

What |Removed |Added
----------------------------------------------------------------------------
Keywords| |triaged

[Ruslan Kabatsayev]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #22 from Ruslan Kabatsayev <***@gmail.com> ---
(In reply to Blase Johnson from comment #21)

Post by Blase Johnson
Does it still take you a long time to open the document with a more recent
version of Okular?

Still 4 seconds with the document from comment 0 on Kubuntu 18.04. And I don't
have any TOC panel open.

[Blase Johnson]

https://bugs.kde.org/show_bug.cgi?id=350798

--- Comment #23 from Blase Johnson <***@outlook.com> ---
I can open that document in about 2 seconds.