Re: Serious Memeory leak in 2.0.30 with IP aliases

Sean McAdam (
Tue, 17 Jun 1997 09:04:44 -0400

At 06:56 PM 6/16/97 -0400, Chris Molnar wrote:
>I don't have a fix, but I am seeing someting simualar in 2.0.29. This is
>also a new "feature". I do not use aliasing, but do use Masquerading. The
>problem has become so noticable that I can not get through compiling the
>kernel source without a problem. The machine is almost useless. The
>problem has gotten worse as I am building up on news messages and innd
>usage. However, I can kill the PID of innd and still have the problem.
>Is it possible to fill swap space and not release it?

Well the reason that I am assuming kernel memory is because the memory
usage brings the buffers and cache down to about 200k each and the swap
only gets up to about 5 Megs ( on a 32 Meg system )

>I am going to try and update to 2.1.42 and see if this helps things.

I'm not ready to make the jump yet, I have been VERY happy with the 2.0.x
performance thus far, with this little exception.

>Please let me know if you come up with a solution!

An Update:
I did a <shift> scroll lock after the system had been up for several
hours. I noticed that the "Network Buffers in use" was growing
constantly. At the time they were at about 32,000 buffers ( This seemed
odd to me. ) At the suggestion of Alexey Kuznetsov I recompiled the
kernel with "RT_CACHE_DEBUG" in route.h set to "2". and adjusted the
"ARP_MAXSIZE" in arp.c back to 256 ( to keep the debug traffic from
arp_force_expire() messages down. )

The result: this seems to have fixed the problem. My Network buffers in
use does not grow constantly. It seems to hover around 1. The only thing
that I can think of is that there is a timing issue with the locking and
unlocking of a resource somewhere that the extra printk()s from the
debugging is fixing.

I know this is not a fix... but it seems to work for now. I will begin to
take out debugging code and see when the problem resurfaces.

If any one has helpful comments on where in the source I can look or some
debugging tricks to try please send them to me.

Thanks for all of your help thus far,

--      @work      @play 

Chief Linux Advocate and HP9000 Systems Admin Guy

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