Network Write Delay using PPPD

Thomas Doerfler Thomas.Doerfler at imd-systems.de
Sat Jun 23 17:42:35 UTC 2001


Hello Mike,

I just had another thought concerning your PPP problem: What kind of 
serial driver do you use? The serial device driver used for PPP 
connections MUST (!) use the new "task-driven" termios interface, and 
currently only few BSPs (if any) support this model. So check the 
device driver, if it uses termios polled or interrupt-driven mode, 
problems are to be expected...

Bye,
	Thomas.


> 
> Hi,
> I am using the i386/pc586 BSP with the latest snapshot.  My code
> is using the standard pppd task to establish a network connection.
> The ppp connection gets established and I can create a socket and 
> connect to my server test application.  
> 
> The RTEMS client code will write a block of data every time it 
> receives some data over the socket.  The problem that I am seeing 
> is that the client write seems to be getting delayed.  And the
> delay keeps getting longer after each successive write.  After four 
> writes, the delay is about 90 seconds!  I have turned off the pppd
> compression options.
> 
> I added some debug statements to the pppd code.  Basically it looks
> like the pppoutput function is getting called immediately but the
> modem_sendpacket function call gets delayed.
> 
> Has anyone seen this problem before?  Any thoughts or suggestions
> would be greatly appreciated.
> 
> Thanks
> Mike Siers


--------------------------------------------
IMD Ingenieurbuero fuer Microcomputertechnik
Thomas Doerfler           Herbststrasse 8
D-82178 Puchheim          Germany
email:    Thomas.Doerfler at imd-systems.de
PGP public key available at: http://www.imd-systems.de/pgp_key.htm



More information about the users mailing list