diff options
Diffstat (limited to 'net/ipv4/tcp_cubic.c')
| -rw-r--r-- | net/ipv4/tcp_cubic.c | 35 |
1 files changed, 8 insertions, 27 deletions
diff --git a/net/ipv4/tcp_cubic.c b/net/ipv4/tcp_cubic.c index 3aa0b23c1ea..eb5b9854c8c 100644 --- a/net/ipv4/tcp_cubic.c +++ b/net/ipv4/tcp_cubic.c @@ -1,12 +1,13 @@ /* - * TCP CUBIC: Binary Increase Congestion control for TCP v2.1 - * + * TCP CUBIC: Binary Increase Congestion control for TCP v2.2 + * Home page: + * http://netsrv.csc.ncsu.edu/twiki/bin/view/Main/BIC * This is from the implementation of CUBIC TCP in * Injong Rhee, Lisong Xu. * "CUBIC: A New TCP-Friendly High-Speed TCP Variant * in PFLDnet 2005 * Available from: - * http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/cubic-paper.pdf + * http://netsrv.csc.ncsu.edu/export/cubic-paper.pdf * * Unless CUBIC is enabled and congestion window is large * this behaves the same as the original Reno. @@ -20,15 +21,10 @@ #define BICTCP_BETA_SCALE 1024 /* Scale factor beta calculation * max_cwnd = snd_cwnd * beta */ -#define BICTCP_B 4 /* - * In binary search, - * go to point (max+min)/N - */ #define BICTCP_HZ 10 /* BIC HZ 2^10 = 1024 */ static int fast_convergence __read_mostly = 1; -static int max_increment __read_mostly = 16; -static int beta __read_mostly = 819; /* = 819/1024 (BICTCP_BETA_SCALE) */ +static int beta __read_mostly = 717; /* = 717/1024 (BICTCP_BETA_SCALE) */ static int initial_ssthresh __read_mostly; static int bic_scale __read_mostly = 41; static int tcp_friendliness __read_mostly = 1; @@ -40,9 +36,7 @@ static u64 cube_factor __read_mostly; /* Note parameters that are used for precomputing scale factors are read-only */ module_param(fast_convergence, int, 0644); MODULE_PARM_DESC(fast_convergence, "turn on/off fast convergence"); -module_param(max_increment, int, 0644); -MODULE_PARM_DESC(max_increment, "Limit on increment allowed during binary search"); -module_param(beta, int, 0444); +module_param(beta, int, 0644); MODULE_PARM_DESC(beta, "beta for multiplicative increase"); module_param(initial_ssthresh, int, 0644); MODULE_PARM_DESC(initial_ssthresh, "initial value of slow start threshold"); @@ -145,7 +139,7 @@ static u32 cubic_root(u64 a) static inline void bictcp_update(struct bictcp *ca, u32 cwnd) { u64 offs; - u32 delta, t, bic_target, min_cnt, max_cnt; + u32 delta, t, bic_target, max_cnt; ca->ack_cnt++; /* count the number of ACKs */ @@ -211,19 +205,6 @@ static inline void bictcp_update(struct bictcp *ca, u32 cwnd) ca->cnt = 100 * cwnd; /* very small increment*/ } - if (ca->delay_min > 0) { - /* max increment = Smax * rtt / 0.1 */ - min_cnt = (cwnd * HZ * 8)/(10 * max_increment * ca->delay_min); - - /* use concave growth when the target is above the origin */ - if (ca->cnt < min_cnt && t >= ca->bic_K) - ca->cnt = min_cnt; - } - - /* slow start and low utilization */ - if (ca->loss_cwnd == 0) /* could be aggressive in slow start */ - ca->cnt = 50; - /* TCP Friendly */ if (tcp_friendliness) { u32 scale = beta_scale; @@ -391,4 +372,4 @@ module_exit(cubictcp_unregister); MODULE_AUTHOR("Sangtae Ha, Stephen Hemminger"); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("CUBIC TCP"); -MODULE_VERSION("2.1"); +MODULE_VERSION("2.2"); |