Re: Decaying Performance under newer apache/mp versions

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On 5/9/05, J.e. Turcotte <jet@xxxxxxx.xxx> wrote:
> Has anyone encountered similar problems?  Does anyone have a deeper
> understanding of the whole apache/mp/perl setup to just ~know~ what these
> symptoms are indicitive of?

I'm sorry if this is completely unrelated, I am somewhat of a mp newbie.

I've been recently bitten by some very similar problems on some
scripts (not mp handlers) where CGI parameters and cookies were
not being read correctly -- sometimes my script was seeing GET
and POST parameters completely unrelated to what the browser sent.
My scripts all looked like:

use strict;
use CGI;
my $cgi =3D new CGI();
sub process {
  my $x =3D $cgi->param('x');
  # ...
}
process();

Because the problem only appears when an apache process
is executing a script for the second time, it is very hard to track
(reducing the number of apache children to 1 is very helpful
for debugging). This problem and many possible solutions
are described in great detail in

http://perl.apache.org/docs/general/perl_reference/perl_reference.html#my__=
_Scoped_Variable_in_Nested_Subroutines

To understand why it is related to scripting in mp, see

http://perl.apache.org/docs/general/perl_reference/perl_reference.html#When=
_You_Cannot_Get_Rid_of_The_Inner_Subroutine

I changed "my $cgi =3D ..." to "local our $cgi =3D ..." and everything
started to work magically.

Ricardo