[Vtd-xml-users] Performance in comparison to libxml2

[John K. - K. I. NL <jk...@in...>]

Hello,

I've been playing with vtdxml for a while now, and my latest experience
is not very encouraging to go on :(...

I have created a file with _lots_ of recurring structures and amounts of
recurring data (about 137 MB), eventually I created a xpath to select
the name of every relation in the 4th role (doesn't really matter).

So, I executed it, with the code included for vtdxml (see vtdxml.c), and
it performed like this:

unims@gxvm1:~/src/xmltest$ time ./test ./jkl.files.xml
'//relation[@tsroln=04]/tsnam1' >> /dev/null

real    0m4.940s
user    0m4.625s
sys     0m0.256s

With 162450 bytes of terminal output.

Then, the horrible thing happened, I used lixml2 with an adjusted
reference xpath-program. (xpath1.c from their website, only with content
retrieval):

unims@gxvm1:~/src/libxmltest$ time ./test ./jkl.files.xml
'//relation[@tsroln=04]/tsnam1' >> /dev/null

real    0m2.545s
user    0m2.201s
sys     0m0.321s

The size of the output was 150808 bytes.

This is an incredible difference, am I doing something wrong? Or did I
have too many expectations of vtd?

Regards,
John Kraal