Ethernet bridge leaking memory

Ethernet bridge leaking memory

[Kostja Siefen]

Hi,

I have a strange problem with ethernet bridging in 2.6.13 which leads to heavy 
slab allocation until memory is completely filled up.

My setup:

HP nx7000 Laptop running Kernel 2.6.13
- RTL 8139 network interface on board (module 8139too)
- PC Card Wired LAN Network Interface (module pcnet_cs)

After modprobing bridge and calling

brctl addbr br0
brctl addif br0 eth0 (RTL 8139)
brctl addif br0 eth2 (PC Card Wired LAN)

the bridge is up and running and works like a charm. Sending some traffic (1 
MB/s is enough) through that bridge leads to massive kernel memory 
allocation. slabtop reports, that "skbuff_head_cache" and "size-2048" eat up 
all the memory (256 MB). This looks like a memory leak to me.

Even unloading the network modules does not free any memory, a reboot is 
required.

Any ideas? 

Yours,

Kostja

Re: Ethernet bridge leaking memory

[Stephen Hemminger]

On Thu, 10 Nov 2005 21:13:27 +0100
Kostja Siefen <kostja@siefen.de> wrote:

> Hi,
> 
> I have a strange problem with ethernet bridging in 2.6.13 which leads to heavy 
> slab allocation until memory is completely filled up.
> 
> My setup:
> 
> HP nx7000 Laptop running Kernel 2.6.13
> - RTL 8139 network interface on board (module 8139too)
> - PC Card Wired LAN Network Interface (module pcnet_cs)
> 
> After modprobing bridge and calling
> 
> brctl addbr br0
> brctl addif br0 eth0 (RTL 8139)
> brctl addif br0 eth2 (PC Card Wired LAN)
> 
> the bridge is up and running and works like a charm. Sending some traffic (1 
> MB/s is enough) through that bridge leads to massive kernel memory 
> allocation. slabtop reports, that "skbuff_head_cache" and "size-2048" eat up 
> all the memory (256 MB). This looks like a memory leak to me.
> 
> Even unloading the network modules does not free any memory, a reboot is 
> required.
> 
> Any ideas? 
> 


Could you try identifying which flow or driver is leaking?

	eth0 ---> eth2
	eth0 ---> br0
	eth2 ---> br0
	eth2 ---> eth0
	br0  ---> eth0
	br0  ---> eth2

Also try without bridge, it may just be a driver leak



-- 
Stephen Hemminger <shemminger@osdl.org>
OSDL http://developer.osdl.org/~shemminger

Re: Ethernet bridge leaking memory

[Ferrari (sent by Nabble.com)]

Hi,

Have you find the answer to this problem?

I also have a bridge setup between a 802.11 wireless interface and a 802.3 interface. When I run UDP traffic at a fast rate, the skbuff_head_cache values goes up and UP..

Could someone throw some light on this.

I am running 2.4.20 kernel on this.

Ravi
--
Sent from the linux-kernel forum at Nabble.com:
http://www.nabble.com/Ethernet-bridge-leaking-memory-t529532.html#a1883148