Open GoogleCodeExporter opened 9 years ago
This is most likely the syntax highlighter that is slowing things down. Try
":syntax off" and see if that makes a
difference.
A problem with XML that I have noticed is that the lines are often very long
and this causes significant slow
downs. I've seen lots of discussions about this on the web but I don't
remember any links (check Vim tip wiki,
vim_use list and google in general).
Original comment by bjorn.winckler@gmail.com
on 15 Jan 2009 at 4:57
Yes, turning off the syntax highlighting makes it fast again.
I tried this on Windows XP with gVIM and 3200x1200 resolution on much slower
machine,
it's as fast as MacVim with syntax highlighting turned off.
I wonder why the Mac version rendering is so much slower.
Original comment by veritas....@gmail.com
on 15 Jan 2009 at 10:57
I don't know why its that much slower on the Mac, but I have seen similar
problems before. There is some part
of the syntax highlighting code inside Vim that compiles to something very
slow. I've tried to profile this but I
have not managed to figure what exactly is so slow, but it seems that some
system libraries on the Mac are just
extremely slow.
At any rate, as far as I can gather the problem is not with the MacVim renderer
but the regexp code in Vim so I
don't know what I can do about it. Still, it might help if you send me the
file that renders slowly so that I can
profile what's going on (you can send it directly to my gmail account).
Original comment by bjorn.winckler@gmail.com
on 15 Jan 2009 at 11:45
I don't know if the problem is with the regexp engine. It is perfectly fine
once you
turn the syntax highlighting off. Would that not indicate that the problem is
in the
rendering code?
I have attached the XML file (it's really Maple 11 style sheet). But you don't
need
this file to reproduce the problem.
Also, the slowness of rendering can be seen by simply browsing help files, e.g.
:h index
and make it the only window. Use the mouse wheel to scroll through it. You can
see
the text being painted.
If you simply page through then it is much faster. But this is a different
problem
and not so in your face, since I assume most people don't drive VIM with a
mouse :D.
Original comment by veritas....@gmail.com
on 17 Jan 2009 at 2:06
Attachments:
Veritas: Vim does its syntax highlighting with regex matches. Try
:e $VIMRUNTIME/syntax/xml.vim
This contains a set of regexen that tell vim how to syntaxcolor xml files.
Bjorn: Since you looked at this, do you have a vague idea where the problem is?
Might adding dtrace probes to
some areas of the regex code help to track this down?
Original comment by nicotha...@gmail.com
on 17 Jan 2009 at 4:11
Nico: I don't really have any idea where the problem is. The only thing I can
say is that every time I'm profiling
the string and regexp functions are taking up most of the time. I once tried
replacing all the multibyte aware
string functions for ones that assumed everything was ASCII and made sure they
could be inlined and this
resulted in a very noticeable speedup, but nothing groundbreaking.
As for "dtrace probes": I've never used them but I vaguely remember that you
posted something about dtrace a
while back. I've only used the Shark app to do profiling so far.
Original comment by bjorn.winckler@gmail.com
on 27 Jan 2009 at 11:39
I just noticed that for some files (e.g. kiwitobes.com/feeds/python_search.xml
) syntax highlighting gets a _lot_
faster if 'cursorline' is not enabled (or the other way round, gets a lot
slower if 'cursorline' is set).
Veritas: Do you have 'cursorline' set? Does disabling it help?
Original comment by nicotha...@gmail.com
on 5 Feb 2009 at 5:44
I don't have cursorline in command line version set, but I do in the GUI
version.
Also, I have noticed that Snapshot 42 has gotten faster than Snapshot 40 (for
which I
reported this bug). CPU usage does not spike either. But it still can't keep up
with
my typing speed. On the other hand it's not as horrible as before.
Original comment by veritas....@gmail.com
on 5 Feb 2009 at 10:21
Original issue reported on code.google.com by
veritas....@gmail.com
on 15 Jan 2009 at 12:41