[ECOS] Sockets getting full..

[ECOS] Sockets getting full..

[James Hunter]

Hi,

We are using a PowerQuicc III (MPC8541@677Mhz - so plenty of grunt)
which is tasked with sending and receiving data over a UDP connection.
The test application is only receiving data from another external UDP
transmitter.

What we are seeing is almost immediately the socket is filling up with
data as if your application is not reading the data back quickly enough.


This test application spins on a Select() waiting to get packets, its
executing around ~10k times per second so fast enough to catch any
packets - we do sleep at the end of this loop.

The sending unit sends around 700 packets per second, however we receive
only around 120 (going on the results returned by Select function).
However the packets received are in order (using a sequence number) so
nothing is dropped, they just appear to fall out of Select really really
slow (we are aiming for a lot more than 700 packets per second from the
HW)

We have also extended MBUFs / Clusters as we originally were running out
at start-up (4Mb is set to the network stuff - we have 128Mb DDR2 on
board).

Any help would be greatly appreciated.

Regards,

James

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Re: [ECOS] Sockets getting full..

[Andrew Lunn]

On Wed, Jun 27, 2007 at 11:25:32AM +0100, James Hunter wrote:
> Hi,
> 
> We are using a PowerQuicc III (MPC8541@677Mhz - so plenty of grunt)
> which is tasked with sending and receiving data over a UDP connection.
> The test application is only receiving data from another external UDP
> transmitter.
> 
> What we are seeing is almost immediately the socket is filling up with
> data as if your application is not reading the data back quickly enough.
> 
> 
> This test application spins on a Select() waiting to get packets, its
> executing around ~10k times per second so fast enough to catch any
> packets - we do sleep at the end of this loop.
> 
> The sending unit sends around 700 packets per second, however we receive
> only around 120 (going on the results returned by Select function).
> However the packets received are in order (using a sequence number) so
> nothing is dropped, they just appear to fall out of Select really really
> slow (we are aiming for a lot more than 700 packets per second from the
> HW)

I think we need to see the code in order to understand this....

  Andrew

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RE: [ECOS] Sockets getting full..

[James Hunter]

> -----Original Message-----
> From: Andrew Lunn [mailto:andrew@lunn.ch] 
> Sent: 27 June 2007 23:45
> To: James Hunter
> Cc: ecos-discuss@ecos.sourceware.org
> Subject: Re: [ECOS] Sockets getting full..
> 
> On Wed, Jun 27, 2007 at 11:25:32AM +0100, James Hunter wrote:
> > Hi,
> > 
> > We are using a PowerQuicc III (MPC8541@677Mhz - so plenty of grunt) 
> > which is tasked with sending and receiving data over a UDP 
> connection.
> > The test application is only receiving data from another 
> external UDP 
> > transmitter.
> > 
> > What we are seeing is almost immediately the socket is 
> filling up with 
> > data as if your application is not reading the data back 
> quickly enough.
> > 
> > 
> > This test application spins on a Select() waiting to get 
> packets, its 
> > executing around ~10k times per second so fast enough to catch any 
> > packets - we do sleep at the end of this loop.
> > 
> > The sending unit sends around 700 packets per second, however we 
> > receive only around 120 (going on the results returned by 
> Select function).
> > However the packets received are in order (using a sequence 
> number) so 
> > nothing is dropped, they just appear to fall out of Select really 
> > really slow (we are aiming for a lot more than 700 packets 
> per second 
> > from the
> > HW)
> 
> I think we need to see the code in order to understand this....
> 
>   Andrew
> 
Hi,

We resolved the issue, appears to be some legacy i2c code that was
causing us problems.

Thanks,

James.

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