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Date: Tue, 30 May 2000 09:36:45 +0100
From: "Koster, K.J." <K.J.Koster@kpn.com>
Subject: RE: system hangs...
To: "'G.B.Naidu'" <gbnaidu@sasi.com>
Cc: freebsd-hackers@FreeBSD.ORG
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> 
> We have made some kernel changes. And accordingly we are
> testing the changes using some user level daemon. After
> sending some packets, the system hangs. The number of
> packets sent before the system hangs varies from time to
> time.
>
What kind of changes? What kind of packets? What kind of deamon? What kind
of kernel?

>
> Could some body tell me how to know what is happening? How
> do I find out the reason for hanging? Is there anyway to get
> such information through some core dump? I have enabled
> taking dumps and it is dumping when the system panics but
> not when it hangs.
>
You can make the system panic manually, and then you have your  kernel core.

As for how to know what's happening: printf() is your friend.

> 
> Is memory leakage can cause a system hang? If so how do I 
> find out that there is a memory leakage?
> 
There are many good books and web sites that cover basic debugging
techniques.

You have to provide a *lot* more information than this. We can only help you
if you are able to produce some detailed description of your problem. If you
can't tell sitting behind the box, how are we supposed to know what you've
done wrong?

    Kees Jan

==============================================
 Everyone is responsible for his own actions,
 and (people tend to forget this) the effect
 they have on others.


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