Re: Running process with grep-find interface is very slow

[Kevin Rodgers]

On 8/31/11 2:18 AM, Tom wrote:
> Tom<adatgyujto<at>  gmail.com>  writes:
> > Why is it so much slower to run the same command via grep than
> > via the command line?
>
> Turns out it was the way I ran the command.
>
> I created a small convenience function which always started the
> search from the root directory of the project
>
>
> (let ((default-directory rootdir))
>    (grep-find (concat "c:/xampp/perl/bin/perl.exe c:/bin/ack -i " pattern)))
>
>
> Looks like default-directory caused the problem, because if I change it
> to this:
>
>    (with-current-buffer (find-file-noselect rootdir)
>      (grep-find (concat "c:/xampp/perl/bin/perl.exe c:/bin/ack -i " pattern)))
>
> then it's not slow anymore.
>
>
> It fixed the problem, though I don't really get the difference. Isn't
> setting default-directory temporarily a usual way to make a directory
> current for the duration of a function?

Yes.  Could you profile the grep-*, compile-*, and compilation-*
functions with elp.el under both scenarios to show where the performance
problem occurs?

--
Kevin Rodgers
Denver, Colorado, USA