[Privoxy-devel] 0007-Create-a-fast-CGI-function

Fri Sep 8 21:05:16 CEST 2023

On Thursday, September 7th, 2023 at 12:06 PM, Fabian Keil wrote:

> I suppose some filled-out templates could be cached as another
> mechanism to speed things up.

But then you'll need to check the cache to see if it's out of date & how do you do that without accessing the disk?

Maybe you can come up with something that is fast; all I could come up with is what I did in cgi_show_url_final_info:
  char body[] = \
  "<!DOCTYPE html><html lang=\"en\"><head><title>URL Block Info</title></head>\n"\
  ... </html>\n";
  ...
  /* return template_fill_for_cgi(csp, "show-url-final-info", exports, rsp);   -LR- */
  rsp->body = strdup_or_die(body);
  template_fill(&rsp->body, exports);
  free_map(exports);
  return 0;

> > I expect it to be noticeably slower when everything is happening
> > on the same machine. I originally had this in my awk program for
> > talking to Privoxy:
> > 
> > print "GET http://config.privoxy.org/show-url-final-info?url=" url " HTTP/1.1" |& webserver
> > print "Host: config.privoxy.org" |& webserver
> > print "Accept: text/html" |& webserver
> > print "Connection: Keep-Alive" |& webserver
> > print "" |& webserver
> > 
> > That's slower than
> > 
> > printf("GET http://config.privoxy.org/show-url-final-info?url=%s HTTP/1.1\r\n"\
> > "Host: config.privoxy.org\r\n"\
> > "Accept: text/html\r\n"\
> > "Connection: Keep-Alive\r\n\r\n", url ) |& webserver
> > 
> > because the multiple print statements tend to cause multiple writes
> > to Privoxy. The single printf causes a single write to Privoxy and
> > is clearly faster.
> 
> That's what I would expect.

Not me.  Or at least, not the me back then :)
I was seeing multiple tcp packets with wireshark and not coming up with a reasonable explanation for why.  It took me a while before trying to do everything in a single write.

> Is your awk program free software and publicly available?

GPL yes. Available, maybe.  I tried to update my github repository and after multiple pushes _finally_ saw something in the contrib directory.
  https://github.com/ler762/privoxy/tree/lee/contrib

Hopefully the "nothing, nothing, nothing, YaY! there it is, nothing, nothing" flakiness was because I'd just updated it and they took _way_ too long to update all their web servers.

Lee