SUMMARY: Launching X copies of an app..?

From: Rick Beebe <richard.beebe_at_yale.edu>
Date: Thu, 15 Apr 1999 09:17:15 -0400

As usual the response from this list was fast and useful. Thank you.

The answers fell into two camps:

Dan Bernstein's tcpserver. It does access control and concurrency limiting
and can be found at http://www.pobox.com/~djb/ucspi-tcp.html.

This was suggested by
 Christopher K Davis <ckd_at_ckdhr.com>
 Simon Greaves <Simon.Greaves_at_usp.ac.fj>
 "Degerness, Mandell ITSD:EX" <Mandell.Degerness_at_gems2.gov.bc.ca>

The somewhat embarrassing thing is that I've had the package on the machine
for quite a while--I use its tcpclient quite a bit. I'd forgotten about
tcpserver.

The other suggestion was xinetd from http://sources.isc.org/network/daemon/
which is an inetd replacement that adds, among other things, concurrency
limits.

That was suggested by
 Richard Stevenson <Richard.Stevenson_at_vuw.ac.nz
 John P Speno <speno_at_isc.upenn.edu>

And finally I got a very helpful pointer from Alan Davis (Davis_at_Tessco.Com):

> You may want to take a look at :
>
> http://www.unix.digital.com/internet/tuning.htm
>
> Alan Davis
> Tru64 Unix Consultant

There's a lot of good stuff on that page. It will take me a while to wade
through it.

I've decided to use tcpserver for now since it's already installed on the
machine. I'm a little reluctant to replace inetd because I'm only have
trouble with this one server. Thanks for all the help. My original message
follows my signature.

-- 
  _______________________________________________________________________
    Rick Beebe                                           (203) 785-6416
    Manager, Systems & Network Engineering          FAX: (203) 785-3978
    ITS-Med Client & Technology Services         Richard.Beebe_at_yale.edu   
    Yale University School of Medicine                                 
    P.O. Box 208078, New Haven, CT 06520-8078
  _______________________________________________________________________
> I have a program that gets launched by inetd (a pop server). Occasionally,
> either from nefarious origins or because of over-rumbunctious clients and a
> somewhat overloaded server I get an enormous build-up of these processes.
> Once it starts and I get more than 600 or so the machine gets slower and
> slower which just exacerbates the problem. Last time it happened there were
> over 2500 of these processes and it was taking 5 minutes for each of my
> interactive commands to execute. I got the machine back by killing inetd and
> eventually the pop processes died off.
> 
> What I would like is a handler daemon that will monitor the pop port like
> inetd does but will only allow a user-specified number of servers to start
> up. Before I tackle writing this I wondered if anyone knew if such a program
> already existed.
> 
> I know that I can tell inetd to limit the number of processes it will fire
> up in any single minute but rate of startup isn't really the problem.

Received on Thu Apr 15 1999 - 16:12:18 NZST