max persistance time?

[Joseph Mack NA3T]

On Thu, 31 Aug 2006, Joseph T. Duncan wrote:

> c)The client shuts down and/or closes inappropriately the real server sits 
> there, leaves the desktop and applications active. now here is were weirdness 
> happens.

thanks for the description.

There is a similar scenario with a web interface to a cgi 
script. I run a map server, which draws a map and returns it 
in a webpage. If the client disconnect (hits "back", kills 
browser, goes elsewhere) while the map is being drawn 
(between submit and getting the map), the map process goes 
to 100% CPU and will run forever. Since I know how long it 
takes to draw a map, I have a cron job which kills any map 
processes that run longer.

This doesn't help you, but you aren't the only one with the 
problem.

> connection happens.. (failer of some kind, wacko config? I 
> don't know I cant really reproduce it, maybe they have 
> some weird retarded personal router appliance at home???)

you may never find out.

> real server kills off the active (but idle) 
> desktop+applications in 1 day (there is a active but idle 
> session autologout after x time setting on the real 
> servers) these clients are the troublesome ones cause if 
> they login a few times they will wind up with a active but 
> idle desktop+application session on each real server

are these idle processes being a resource hog? If not, can 
you just put up with an app in a deranged but otherwise 
harmless state?

Can you differentiate the sessions you don't want from the 
ones that you want to stay idle? eg look in netstat to see 
if you have multiple sessions from one IP? (probably won't 
work, a whole bunch of people could be coming in through a 
proxy).

> *some of these issues would be addressed by l7 balancing 
> but currently the only commercial products that can do l7 
> balancing cost big $$$.

There is L7 code on the LVS website. It's experimental and 
few people have used it, so you'll have to figure it out 
yourself.

> ipvsadm is started from a linked init script in /etc/rc2.d 
> it loads its saved rules from /etc/ipvsadm.rules
>
> so can I place --set x y z in /etc/ipvsadm.rules?

I don't use a rules file, but presumably it does the same 
thing as running ipvsadm commands, so "yes".

> this didn't seem appropriate cause ipvsadm wont dump the 
> change their when it rewrites that file upon a shutdown.

I don't know what changes you want to put in there, but I 
expect you could have a script update /etc/ipvsadm.rules.


Joe
-- 
Joseph Mack NA3T EME(B,D), FM05lw North Carolina jmack 
(at) wm7d (dot) net - azimuthal equidistant map generator at 
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