[commonsguy]

I use ebook-convert to take a book that I wrote, in an HTML format, and generate an EPUB. I use the following switches:

--page-breaks-before
--disable-unwrap-lines
--chapter
--chapter-mark
--authors
--isbn
--publisher
--title
--pubdate
--extra-css
--cover
--no-svg-cover

(though, in some experimentation, none of those seem to be affecting my problem)

I used to use ebook-convert 0.8.8 on Ubuntu Linux 11.04. Generating the EPUB took a couple of minutes.

I am now attempting to use ebook-convert 1.6.0 on Ubuntu Linux 13.04. Things run *much* more slowly:

44 chapters = 144 seconds
50 chapters = 289 seconds
57 chapters = 433 seconds
78 chapters = 1923 seconds

Here, the chapter counts refer to the first N chapters out of my book. I am estimating that generating the entire 172-chapter book will take 6-7 hours... whereas it used to take a couple of minutes with v0.8.8 of ebook-convert.

If I add -v -v -v, almost all of the time is spent in "Flattening CSS and remapping font sizes...". Once we get through that and onto "Source base font size is 12.00000pt", the process will wrap up in a handful of seconds. And, even if I get rid of all of those switches that I listed, things are still slow, suggesting that it's not getting clogged up because of something that I have opted into.

Note that memory is not an issue -- I have 8GB, and memory usage is not steadily ramping up. Also, the computer has a quad-core Intel i7 CPU and so is not lacking for horsepower.

Any idea what might be going on here? And, more importantly, any idea if there is some switch that I can add that will return things to something more closely resembling the previous speed?

Thanks!