script making zombies and killing server

[mikeseo]

I am using a random text cgi script heavily on my webpages and it is creating zombie defunct processes, hundreds of them. They are lagging the server so bad I have to reboot. Is there a random script that can handle heavy usage and not create zombies? I think the zombies are happening when webpage is closed before script is done running?

[moltar]

try exiting the script explicitly.

exit(0);

[mikeseo]

I replaced exit; with exit(0); but still got zombies. I read something about having to do double forking to avoid zombies?

[mikeseo]

found this code?

If you fork() without ever waiting on your children, you will accumulate zombies:

$SIG{CHLD} = sub { wait };

There's also the double-fork trick (error checking on fork() returns omitted);

unless ($pid = fork) {
unless (fork) {
exec "what you really wanna do";
die "no exec";
# ... or ...
## (some_perl_code_here)
exit 0;
}
exit 0;
}
waitpid($pid,0);

[moltar]

for random text you don't really need to fork anything. what is your exact setup? is the code long? can you post a sample?

[mikeseo]

#!/usr/bin/perl

######################################################################
# Necessary Variables: #
# The following variables should be set to define the locations #
# and URLs of various files, as explained in the documentation. #

#---Modification by Ron Perry aka ronzta
use CGI;
$cgi = new CGI;
my $RandomTextFile = $cgi->param('file');

#$RandomTextFile = "randomtext.txt";
# En: Path of Text file.
# Fr: Chemin du fichier de textes.
#----end of modified code------

$Delimiter = "\n--NEXT--\n*"; # En: Tags for Next Texte.
# Fr: Separateur de texte.

# Options:
$UseLog = 0; # Use Log File? 1 = YES; 0 = NO
$LogFile = "/Absolute/path/to/Random-Text-Log.txt";

# Nothing Below this line needs to be altered! #
######################################################################

srand(time);
open(LINKS,"$RandomTextFile") ¦¦ &Error("Cannot Open Links File : $RandomTextFile, Error $!\n");
@TextFile = <LINKS>;
close(LINKS);

$NbLines = @Text = split(/$Delimiter/, join('',@TextFile));
$Phrase = $Text[int rand $NbLines];

if ($UseLog) {
@date = localtime(time); $date[4]++; $date[5] += 1900;
$Time = "$date[4]/$date[3]/$date[5]";
open(LOG,">>$LogFile") ¦¦ &Error("Cannot Write Log File : $LogFile, Error $!\n");
print LOG "[$Time] - $ENV{'REMOTE_HOST'} -> $Url\n";
close(LOG);
}

print "Content-type: text/html\n\n";
print $Phrase."\n";

exit(0);
sub Error {
my($ErrorText) = @_;
print "Content-type: text/html\n\n";
print "Error: ".$ErrorText;
exit(0);
}

[edited by: jatar_k at 8:27 am (utc) on Feb. 11, 2005]
[edit reason] removed urls [/edit]

[mikeseo]

I am loading this 6 times per webpage and have a couple thousand webpages.

[rocknbil]

Well I really don't have a clue, looks good from here, but if I were to debug I'd first revert to the hard-coded $RandomTextFile version you have commented out and see if it persists. If that doesn't work, turn the logging off, see if it persists. If THAT doesn't work, I'd eliminate the use CGI and put a small read/parse routine in it's place (You're only grabbing one key anyway.) It's not likely, but maybe it's the module that's causing the process.

Also srand doesn't really need a seed, but it shouldn't cause that either . . .

[lexipixel]

If you are calling this CGI as an SSI from an HTML page, you can't pass a query to the script, ie-

This works:

<!--#exec cgi="/cgi-bin/randomx.cgi" -->

This doesn't:

<!--#exec cgi="/cgi-bin/randomx.cgi?file=abc.txt" -->

To use multiple input text files you'll need a script for each, hardcoded with the appropriate file name.

.

[PhraSEOlogy]

Just to add another angle on this problem.

I sometimes generate multiple templates of the same page with unique text on each copy. I then choose a random template for the page. You will need to read in the template (i/o overhead) but its better than getting zombies all over the place.

[rocknbil]

this doesn't

<!--#exec cgi="/cgi-bin/randomx.cgi?file=abc.txt" -->

lexipixel is that just on an exec? Because I have it working fine as an include

<!--#include virtual="cgi/ads.cgi?grp=2" -->

Of course, the script has to print out appropriate headers (or not) depending on how it's used.