Commit:     a357dde9df33f28611e6a3d4f88265e39bcc8880
Parent:     5e5234ff17ef98932688116025b30958bd28a940
Author:     Stephen Hemminger <[EMAIL PROTECTED]>
AuthorDate: Fri Nov 30 01:10:55 2007 +1100
Committer:  Herbert Xu <[EMAIL PROTECTED]>
CommitDate: Fri Nov 30 01:10:55 2007 +1100

    [TCP] illinois: Incorrect beta usage
    Lachlan Andrew observed that my TCP-Illinois implementation uses the
    beta value incorrectly:
      The parameter  beta  in the paper specifies the amount to decrease
      *by*:  that is, on loss,
         W <-  W -  beta*W
      but in   tcp_illinois_ssthresh() uses  beta  as the amount
      to decrease  *to*: W <- beta*W
    This bug makes the Linux TCP-Illinois get less-aggressive on uncongested 
    hurting performance. Note: since the base beta value is .5, it has no
    impact on a congested network.
    Signed-off-by: Stephen Hemminger <[EMAIL PROTECTED]>
    Signed-off-by: Herbert Xu <[EMAIL PROTECTED]>
 net/ipv4/tcp_illinois.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/net/ipv4/tcp_illinois.c b/net/ipv4/tcp_illinois.c
index 64f1cba..5aa5f54 100644
--- a/net/ipv4/tcp_illinois.c
+++ b/net/ipv4/tcp_illinois.c
@@ -298,7 +298,7 @@ static u32 tcp_illinois_ssthresh(struct sock *sk)
        struct illinois *ca = inet_csk_ca(sk);
        /* Multiplicative decrease */
-       return max((tp->snd_cwnd * ca->beta) >> BETA_SHIFT, 2U);
+       return max(tp->snd_cwnd - ((tp->snd_cwnd * ca->beta) >> BETA_SHIFT), 
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