My question is very straightforward, Why XeLateX is slower than pdfLaTex, and some times has a long pause before running the main file?
I know XeTeX/XeLaTeX has to load a lot of packages, but why, once a while, it stops for a long time after the last file loaded?
and further more why after starting to compile the pages, the average speed of XeTeX's page processing is slower than the average speed of pdfTeX's page processing?
xetex is an extension of TeX, not pdflatex, so after xetex has run it needs to run a separate dvi driver program to convert the generated dvi file (extended dvi known as xdv) to postscript. By default this driver (xdvipdfmx) is called automatically, but on large documents can account for a notcable pause after the final tex message on the terminal.
The above accounts for any "final pause", but otherwise xetex is in general slower than pdftex (and faster than luatex) they are different systems working with different font technologies and different character data structures so you would expect some differences.
