Why is `borb` so (incredibly) slow? about borb HOT 4 CLOSED

Thanks for your feedback.
I'd love to know what takes up most of the time.
If you can dig deeper and perhaps perform a trace to see which functions are the most labor-intensive, that'd be great.

Kind regards,
Joris Schellekens

from borb.

Thanks for your response.

For this little benchmark, for every PDF library, the goal was to see how long it would take to get a simple page count. For borb, I benchmarked the following code:

def get_page_count_borb(file: Path) -> int:
    with open(file, "rb") as f: 
        doc = PDF.loads(f)
        return doc.get_document_info().get_number_of_pages()

I'll see if I can narrow it down further soon.

from borb.

I think one of the first things to remark there is that for borb, there is no difference between getting a page-count and getting the text from all pages.

The entire binary stream is converted to the internal representation when you're loading a Document.

I imagine some libraries might optimize that, and only parse the needed things to get the page-count.

from borb.

I changed the code around a bit.
Rather than always parsing the content of the page, a page is now only parsed if there is actually a registered EventListener. In other words, if the content of the page is not needed by anyone, it isn't parsed.

This still allows you to open / copy / modify documents. And of course to read their metadata (such as number of pages).
This should provide a significant speed-up.

These are my findings. The corpus I used can be found here.

output.pdf

Kind regards,
Joris Schellekens

from borb.