«

Hello All!

Look at the following pseudo-code:

....
....
while(1)
{
while( $client = $server->accept )
{
next if fork;
# Child code here
print "New client\n";

# Arbitrary perl code (work with Oracle via DBI, logging,
request processing, etc)

exit;
}
}
....
....

As you can see this is a part of TCP server.
My server dies after some time
I see message about Oracle critical error in my log (this is the last
message).
It's very strange because all work with Oracle is performed in _child_
process!

I can't understand how can parent process die!
It may happen only if accept dies, since parent process calls only
accept and fork
in its main loop.

Any ideas?

On 2007-01-15, <> wrote:
> Hello All!
>
> Any ideas?

Yeah, post some code.

Justin.

--
Justin C by the sea.

writes:

> My server dies after some time

And so it should; it has at least 2 bugs (as posted).

> I can't understand how can parent process die!

Hint: what happens when fork fails ?

The reason fork should fail (given your pseudo-code):
from "perldoc -f fork":

If you "fork" without ever waiting on your children, you will
accumulate zombies.

Hint: zombies exhaust your per-user process limit, and kernel
process table.

Cheers,
--
In order to understand recursion you must first understand recursion.
Remove /-nsp/ for email.

Paul Pluzhnikov <ppluzhnikov-> wrote:

> Hint: zombies exhaust your per-user process limit, and kernel
> process table.

And they eat the flesh of the living...

--
John Experienced Perl programmer: http://castleamber.com/

Perl help, tutorials, and examples: http://johnbokma.com/perl/

John Bokma wrote:
> Paul Pluzhnikov <ppluzhnikov-> wrote:
>
> > Hint: zombies exhaust your per-user process limit, and kernel
> > process table.

It's impossible.
There is SIGCHLD handler in my code.
ps output doesn't show any zombies.

>
> And they eat the flesh of the living...
>
> --
> John Experienced Perl programmer: http://castleamber.com/
>
> Perl help, tutorials, and examples: http://johnbokma.com/perl/

Krivenok Dmitry <> wrote in comp.lang.perl.misc:
>
> John Bokma wrote:
> > Paul Pluzhnikov <ppluzhnikov-> wrote:
> >
> > > Hint: zombies exhaust your per-user process limit, and kernel
> > > process table.
>
> It's impossible.
> There is SIGCHLD handler in my code.
> ps output doesn't show any zombies.

The show your code (reduced to a minimum that still exhibits the
problem). Pseudo-code will only give you pseudo-answers.

Anno