> I tried to find the reason in my LaTeX header uasge.
> If I ban the usage of #+LATEX_HEADER: \usepackage{mathpazo}, the test
> time reduced to 3.5s. (I love this font set)
> If I ban the fontenc + mathpazo, it remains 3.5s.
> If I ban the lmodorn + fontenc + mathpazo, it reduces to 1.9s.
This is probably the cause. 1.9 seconds for 700 fragments sounds about
right on a 5800.
> Other packages like tikz, geometry, stmaryrd do not affect the result
> time notably.
> Maybe deleting my all newcommands and declareMathoperator (about 20
> headers) will decrease the time more? But without them, I need to
> rewrite this org file to make the compilation successfully. So I
> haven't attempted it yet.
You can use
#+latex_header_extra: \usepackage{...}
to include it when exporting the file to PDF, but exclude it from LaTeX
preview compilation. This way you can have reasonably fast previews but
still export it with all packages.
Karthik
