Donovan as of your suggestion we have done the following changes The API calls, in DNA mode, return the following errors:
#define GENERIC_DNA_ERROR -1 #define END_OF_DEMO_MODE -2 #define NO_TX_SLOT_AVAILABLE -3 So if you get -3 from the send function you know that you are sending faster than the NIC can send or the receiver can receive. In fact ethernet is a point-to-point communication, thus in case of fast senders the receiver sends back ethernet pause frames for slowing down the sender. This means that a slow receiver can slow down a fast sender Cheers Luca On Oct 19, 2011, at 6:52 PM, Don Provan wrote: > In general, I'd like to see pfring routines return an errno. > That often helps in debugging any issues, particularly in > cases such as the DNA library where I can't go in and look > at the code. pfring_send() is a particular problem because > there's no way for the calling code to distinguish "you screwed > up" from "everything's fine, you just need to try again later". > -don > > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of Luca Deri > Sent: Wednesday, October 19, 2011 1:39 AM > To: [email protected] > Cc: <[email protected]> > Subject: Re: [Ntop-misc] Using DNA devices,pfring_send() sometimes fails > to a ring that's also receiving > > Don > Would that help if we would return a different value for "no slot > available" ? > > Regards Luca > > Sent from my iPad > > On 19/ott/2011, at 01:58, "Don Provan" <[email protected]> wrote: > >>> pfring_send() returns -1 when there are no slots available in the TX >> ring >> >> OK, thanks. It's good to know that's the only possible failure. >> Of course, it also return -1 when there's no send dispatch point, >> but I knew that wasn't the case. What happens within the DNA >> send routine was out of my vision. >> >>> No, it's just a possible design choice >> >> I'll keep it in mind. >> -don >> _______________________________________________ >> Ntop-misc mailing list >> [email protected] >> http://listgateway.unipi.it/mailman/listinfo/ntop-misc > _______________________________________________ > Ntop-misc mailing list > [email protected] > http://listgateway.unipi.it/mailman/listinfo/ntop-misc > _______________________________________________ > Ntop-misc mailing list > [email protected] > http://listgateway.unipi.it/mailman/listinfo/ntop-misc --- We can't solve problems by using the same kind of thinking we used when we created them - Albert Einstein _______________________________________________ Ntop-misc mailing list [email protected] http://listgateway.unipi.it/mailman/listinfo/ntop-misc
