problem with ethertap

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problem with ethertap

mirkomassi
 I have a problem with ethertap!... I have an application on eCos that transmitt
a lot of packets, packet size = 1012 bytes,
 and i have an application on Linux that must receive these packages, but
if the number of packets that transmit for example
 is ten, application on linux receive one packet only, and if the transmit
is in loop, i don't receive null.
 This is my ethernet.tdf:
 synth_device ethernet {
    ## Map eCos devices on to Linux ones.

     eth0 ethertap

    ## Maximum number of packets that should be buffered per interface.
    ## Default 16
    max_buffer 32

}

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Re: problem with ethertap

Bart Veer
>>>>> "mirkomassi" == mirkomassi  <[hidden email]> writes:

    >  I have a problem with ethertap!... I have an application on
    > eCos that transmit a lot of packets, packet size 1012 bytes, and
    > i have an application on Linux that must receive these packages,
    > but if the number of packets that transmit for example is ten,
    > application on linux receive one packet only, and if the
    > transmit is in loop, i don't receive null.

Is this traffic TCP or UDP? If TCP then ordinary TCP/IP windowing
should take care of flow control and nothing should get lost. If UDP
then that is inherently an unreliable protocol and packets may be
discarded on either the eCos side or the Linux side whenever they are
inconvenient. However normally there is enough buffering capacity in
various places to avoid problems.

First you will have to figure out where the packets are being lost:
inside eCos, by the synthetic target, or inside Linux. A good step
would be to enable ethernet traffic logging in the synthetic target.
If the packets never reach the host-side I/O auxiliary then the
problem must be on the eCos side and you may have to configure the
TCP/IP stack with more buffer space. If the packets do reach the
host-side then further investigation will be needed.

Bart

--
Bart Veer                       eCos Configuration Architect
http://www.ecoscentric.com/     The eCos and RedBoot experts


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