Messages in this thread | | | Date | Wed, 31 Jan 2001 10:19:25 +0100 | From | Martin Rauh <> | Subject | Re: Packet loss in IP/UDP Stack? |
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The UDP packet loss went away by setting the rmem_max and rmem_default in /proc/sys/net/core on the receiving linux box to about 80 percent of the size of the transfered file (~50MB).
Many thanks for the fast help!
greetings,
Martin Rauh
Andi Kleen wrote:
> On Fri, Jan 26, 2001 at 07:01:12PM +0100, Martin Rauh wrote: > > Hi folks, > > > > It seems that we are loosing packets in the UDP stack. > > Somebody might think that this is not astonishing, but > > the packets are not lost at the network layer. They seem to get > > lost in the IP/UDP Layer of the receiving box. > > > > We have got the following configuration: > > Two linux boxes (P4, 733 MHz, 256 MB RAM, kernel 2.4.0) > > are directly connected with two syskonnect sk98xx > > gigabit ethernet cards. We are sending a file from one host to the other > > > > with UDP. About half of the file is lost in the receiving application. > > But according to the statistics in /proc/net/dev no errors (fifo, frame, > > dropped...) > > occured in the network layer. Even the transmitted and received > > data at the network layer (tx-bytes, -packets) are identical > > to the amount of the transfered file (plus network overhead). > > > > Doas anybody know where the loss occurs? Is there a loss at the > > network layer or in the higher protocol layers? > > UDP by default has 64K buffer and drops packets when it overflows. > You can check that using netstat -s. > You can increase it use the SO_{SND,RCV}BUF socket options and/or the > net/core/[rw]mem_* sysctls. > > -Andi > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > Please read the FAQ at http://www.tux.org/lkml/
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/
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