Hi,

On Sat, 14 Mar 2009, Junio C Hamano wrote:

> Johan Sørensen <johan@johansorensen.com> writes:
> 
> >> Do you run git-daemon from inetd, or standalone, by the way?
> >
> > Standalone.
> >
> >> I am wondering how well it would scale if you spawn an external 
> >>"filter path" script every time you get a request.
> >
> > A quick test of 250 consecutive requests with ls-remote to localhost
> > (all without the --verbose flag), slowest run:
> > - Baseline (no --filter-path agument): 3.39s
> >
> > $ cat filter.c
> > #import "stdio.h"
> > int main (int argc, char const *argv[]) {
> > 	printf("%s", "/existing.git\0");
> > 	return 0;
> > }
> > - 3.84s
> >
> > $ cat filter.rb
> > #!/usr/bin/ruby
> > print "/existing.git\0"
> > - 4.76s
> >
> > So, obviously highly dependent on how long it takes the script to 
> > launch and how much work it does. And yes, neither of the above really 
> > does anything :) nor takes any increased cpu load into account
> >
> > Another approach is to keep the external script running and feed it on 
> > stdin, but that would involve a bit more micro-management of the 
> > external process. I will revisit that idea if I find out that's 
> > needed.
> 
> I actually was hoping (especially we have Dscho on Cc: list) that somebody
> like you would start suggesting a "plug in" approach to load .so files,
> which would lead to a easy-to-port dso support with the help from msysgit
> folks we can use later in other parts of the system (e.g. customizable
> filters used for diff textconv, clean/smudge, etc.)

I do not like that at all.  Dynamic libraries -- especially on Windows -- 
are a major hassle.

However, I cannot think of anything Johan might want to do that would not 
be possible using a bunch of regular expressions together with 
substitions.

FWIW I have experimental code in my personal tree that sports 
strbuf_regsub(), a function to replace matches of a regular expression 
(possibly with groups) by a given string (which may contain \0 .. \9, 
being replaced with the respective group's contents).

Ciao,
Dscho