I found it linum mode that slows all things down.
Thank you for the help!
Qiang

On Wed, Jun 17, 2015 at 3:51 AM, Nicolas Goaziou <mail@nicolasgoaziou.fr>
wrote:

> Hello,
>
> Q <godblessfq@gmail.com> writes:
>
> > I am view this file
> > http://doc.norang.ca/org-mode.org
> >
> > It's a prettey long document, when it all folded up, navigating to
> previous
> > line and next line takes about 2 seconds. When the sub heading is shown,
> > it's more responsive. Is this a bug?
>
> I don't know. What Org version are you using? Could you use a profiler
> and report results?
>
>
> Regards,
>
> --
> Nicolas Goaziou
>