https://bugs.documentfoundation.org/show_bug.cgi?id=133976

--- Comment #17 from Alexandre Sena Coelho <[email protected]> ---
(In reply to Buovjaga from comment #15)
> (In reply to Alexandre Sena Coelho from comment #13)
> > This analysis leads to the hypothesis that there may be an optimization
> > issue during export when using the "Fixed" Layout Method.
> > The next step would be to analyze the EPUB export routine with the Fixed
> > Layout Method to identify possible optimization issues.
> 
> Ok, note that peformance issues should normally be investigated with a build
> that does not have debug features enabled. For performance issues I have
> another build that only has the --enable-symbols option, so I can still get
> perf traces:
> https://wiki.documentfoundation.org/Development/
> How_to_debug#Performance_debugging_(perf)
> 
> My flamegraph in comment 2 is from 2020, so probably a good first step would
> be to get a fresh one and look at where the time is spent now.

Thank you for your response, Buovjaga.
I checked the information in the link you provided, and these are indeed
essential tools for this type of analysis.
I also generated a new FlameGraph (flamegraph20250105.svg) using the latest
available version (Build ID: f23af7a56dda5aabe8ba3616566fbfe75805759f).

This issue seems to be more complex than what my current beginner-level skills
with the project allow me to handle.
I suspect that the problem might be related to recalculating the layout of all
previous pages whenever a new page is processed — but this is just a
hypothesis.
To work on this directly, I would need to better understand how rendering,
pagination calculation, cursors, and other technical details work.

One thing I noticed — and I’m not sure if it’s relevant — is that, between
builds a9966e81381059a3a9d8fc4d391ba17d99385fee and
f23af7a56dda5aabe8ba3616566fbfe75805759f, the processing time increased
significantly.

I could try to set up a test suite to compare the performance of EPUB export
with the Fixed Layout across different builds, using a diverse set of documents
as samples. Would that be useful? I’m not sure if something like this already
exists.

-- 
You are receiving this mail because:
You are the assignee for the bug.

Reply via email to