On 12/02/14 13:54, Felix Fietkau wrote: > On 2014-02-12 13:12, Antonio Quartulli wrote: >> On 12/02/14 10:12, Andrew Lunn wrote: >>> On Tue, Feb 11, 2014 at 01:48:15PM +0100, Antonio Quartulli wrote: >>>> From: Antonio Quartulli >>>> >>>> In case of a unused link, the throughput estimation will >>>> get stuck to the last sampled value and therefore the >>>> reported metric will becomes obsolete. >>>> >>>> Send unicast ELP packets to each neighbor to trigger throughput >>>> sampling on unused links. >>> >>> Humm, i can understand the need for this, but i really think the rate >>> control code should be sending the probes, not batman. What do the >>> wifi people say about this? Have they tried submitting patches to >>> them? >> >> I am CC'ing Felix so that he can give his opinion. >> But last time I checked Minstrel I realised that it uses data packets to >> probe rates (there is not a specific probing packet), meaning that if >> there is no data packet to send, then no probing is performed. > Correct. Minstrel never sends dedicated probing packets. Changing > minstrel to send active probing packets to serve the needs of batman > would be a very bad idea, because pretty much all regular users do not > have any need for extra probing. > >> Sending this ELP packets (when there is no unicast traffic) is a way to >> trigger this mechanism in Minstrel. > Right. If I remember correctly, if you send less than 1 packet per 100 > ms, then all packets should end up being probing packets. If that > doesn't work, we can change minstrel's probing pattern to allow things > like batman to get a desirable amount of rate control probing simply by > sending unicast packets. This is what I am trying to achieve here: if no unicast packets have been sent for the last 100ms (at least) then send N probing packets in a row (with N = 2 at the moment - it is a define in main.h). Thanks Felix! Cheers, -- Antonio Quartulli