This performs two optimisations for the recomputation of the sending rate.
1) Currently the target sending rate X_calc is recalculated whenever
a) the nofeedback timer expires, or
b) a feedback packet is received.
In the (a) case, recomputing X_calc is redundant, since
* the parameters p and RTT do not change in between the
reception of feedback packets;
* the parameter X_recv is either modified from received
feedback or via the nofeedback timer;
* a test (`p == 0') in the nofeedback timer avoids using
a stale/undefined value of X_calc if p was previously 0.
2) The nofeedback timer now only recomputes a timestamp when p == 0.
This is according to step (4) of [RFC 3448, 4.3] and avoids
unnecessarily determining a timestamp.
A debug statement about not updating X is also removed - it helps very
little in debugging and just clutters the logs.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>