skbuf problem - Linux

This is a discussion on skbuf problem - Linux ; Hello all, I wonder what make skbuf exhausted - asymetric routing, many syn packets, traffic flood(many pps) ???? I have two linux firewals. One(A) of both has skbuf problem. Sometimes there is no skbuf, so I can see a lot ...

+ Reply to Thread
Results 1 to 2 of 2

Thread: skbuf problem

  1. skbuf problem

    Hello all,

    I wonder what make skbuf exhausted - asymetric routing, many syn
    packets, traffic flood(many pps) ???? I have two linux firewals.
    One(A) of both has skbuf problem. Sometimes there is no skbuf, so I
    can see a lot of RX dropped packets and network is down as well.
    It's really weird becuase the other machine(B) normally is under
    heavy
    traffic than A machine but it's working properly and there is no
    issue
    like that skbuf is exhausted.
    Any idea what caused skbuf exhaust and how to fix it?


    cat /proc/net/skb_stat
    Limit Remaining Dropped.
    40000 0 3290123


    Thanks,
    Dimitri


  2. Re: skbuf problem

    Dimitri.Kim@gmail.com wrote:

    > Hello all,
    >
    > I wonder what make skbuf exhausted - asymetric routing, many syn
    > packets, traffic flood(many pps) ???? I have two linux firewals.
    > One(A) of both has skbuf problem. Sometimes there is no skbuf, so I
    > can see a lot of RX dropped packets and network is down as well.
    > It's really weird becuase the other machine(B) normally is under
    > heavy
    > traffic than A machine but it's working properly and there is no
    > issue
    > like that skbuf is exhausted.
    > Any idea what caused skbuf exhaust and how to fix it?
    >
    >
    > cat /proc/net/skb_stat
    > Limit Remaining Dropped.
    > 40000 0 3290123
    >
    >
    > Thanks,
    > Dimitri


    skbs get allocated as needed, so you need to run
    out of kernel memory to run out of skbs.

    However, the large number of dropped packets when this
    happens suggests a skb leak somewhere in the kernel or
    driver. Those dropped skbs add up to about 100-600MB of
    memory.

    It is quite common that error handling code has more bugs
    than other code. Your case looks like the packet dropping
    code does not free the skbs properly.

    Kind regards,

    Iwo


+ Reply to Thread