Hi All,

I have a problem that I cannot resolve. Some script, called as CGI, prints "Out of memory!" to the stderr. However, the same script does not display that error if run from the command line.

I could not isolate the problem to a simple test case; the problem does not occur for a simpler script.

The script calls another script ("worker") via open(). The other script forks and executes some "daemon" script. The problem does not occur without calling that daemon: 

my $pid = fork;
unless (defined($pid))     {
    return -1;
}
if ($pid != 0)     { # parent
    return 1;        }                                      
        
         POSIX::setsid();                             
close(STDIN);close(STDOUT);close(STDERR);
fork() && exit 0;
exec("$command") or return 0;

[download]
The limits on the host are the following:
bash-3.00# ulimit -a

core file size (blocks, -c) unlimited
data seg size (kbytes, -d) unlimited
file size (blocks, -f) unlimited
open files (-n) 1024
pipe size (512 bytes, -p) 10
stack size (kbytes, -s) 8192
cpu time (seconds, -t) unlimited
max user processes (-u) 29995
virtual memory (kbytes, -v) unlimited

prstat and top displays up to 33M of memory occupied by the scripts.

When I added some trace messages, the "Out of memory!" message was written after the last command of the "worker" script.

I also tried running truss to trace the worker process. It didn't help too much:
worker: ending main
write(2, " w o r k e r : e n d i".., 19) = 19
worker ending
write(2, " w o r k e r e n d i n".., 13) = 13
setcontext(0xFFBFEAE0)
Out of memory!
write(2, " O u t o f m e m o r".., 15) = 15

Printing the text "worker ending" is the last instruction of the script: 

print STDERR "worker ending";
exit 0;

[download]

Do you have any ideas, what next should I do? What could be the root of the problem? What tools could be helpful to trace it?

Thanks in advance,
pkal

In reply to Out of memory! in CGI by pkal

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