aboutsummaryrefslogtreecommitdiffstats
path: root/net/ipv4/tcp_cubic.c (follow)
AgeCommit message (Collapse)AuthorFilesLines
2007-06-13[TCP]: Set initial_ssthresh default to zero in Cubic and BIC.David S. Miller1-1/+1
Because of the current default of 100, Cubic and BIC perform very poorly compared to standard Reno. In the worst case, this change makes Cubic and BIC as aggressive as Reno. So this change should be very safe. Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[TCP]: Congestion control API update.Stephen Hemminger1-1/+1
Do some simple changes to make congestion control API faster/cleaner. * use ktime_t rather than timeval * merge rtt sampling into existing ack callback this means one indirect call versus two per ack. * use flags bits to store options/settings Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[TCP]: cubic update for net-2.6.22Stephen Hemminger1-3/+5
The following update received from Injong updates TCP cubic to the latest version. I am running more complete tests and will have results after 4/1. According to Injong: the new version improves on its scalability, fairness and stability. So in all properties, we confirmed it shows better performance. NCSU results (for 2.6.18 and 2.6.20) available: http://netsrv.csc.ncsu.edu/wiki/index.php/TCP_Testing This version is described in a new Internet draft for CUBIC. http://www.ietf.org/internet-drafts/draft-rhee-tcp-cubic-00.txt Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[TCP]: cubic optimizationStephen Hemminger1-11/+39
Use willy's work in optimizing cube root by having table for small values. Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[TCP] tcp_cubic: faster cube rootStephen Hemminger1-11/+5
The Newton-Raphson method is quadratically convergent so only a small fixed number of steps are necessary. Therefore it is faster to unroll the loop. Since div64_64 is no longer inline it won't cause code explosion. Also fixes a bug that can occur if x^2 was bigger than 32 bits. Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[NET]: div64_64 consolidate (rev3)Stephen Hemminger1-23/+0
Here is the current version of the 64 bit divide common code. Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-12[TCP]: Use read mostly for CUBIC parameters.Stephen Hemminger1-10/+10
These module parameters should be in the read mostly area to avoid cache pollution. Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-10[NET] IPV4: Fix whitespace errors.YOSHIFUJI Hideaki1-25/+25
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-10-25[TCP] cubic: scaling errorStephen Hemminger1-3/+3
Doug Leith observed a discrepancy between the version of CUBIC described in the papers and the version in 2.6.18. A math error related to scaling causes Cubic to grow too slowly. Patch is from "Sangtae Ha" <sha2@ncsu.edu>. I validated that it does fix the problems. See the following to show behavior over 500ms 100 Mbit link. Sender (2.6.19-rc3) --- Bridge (2.6.18-rt7) ------- Receiver (2.6.19-rc3) 1G [netem] 100M http://developer.osdl.org/shemminger/tcp/2.6.19-rc3/cubic-orig.png http://developer.osdl.org/shemminger/tcp/2.6.19-rc3/cubic-fix.png Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[TCP] Congestion control (modulo lp, bic): use BUILD_BUG_ONAlexey Dobriyan1-1/+1
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel1-1/+0
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-17[TCP]: Minimum congestion window consolidation.Stephen Hemminger1-6/+0
Many of the TCP congestion methods all just use ssthresh as the minimum congestion window on decrease. Rather than duplicating the code, just have that be the default if that handle in the ops structure is not set. Minor behaviour change to TCP compound. It probably wants to use this (ssthresh) as lower bound, rather than ssthresh/2 because the latter causes undershoot on loss. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03[TCP] cubic: use Newton-RaphsonStephen Hemminger1-54/+39
Replace cube root algorithim with a faster version using Newton-Raphson. Surprisingly, doing the scaled div64_64 is faster than a true 64 bit division on 64 bit CPU's. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03[TCP] cubic: precompute constantsStephen Hemminger1-76/+57
Revised version of patch to pre-compute values for TCP cubic. * d32,d64 replaced with descriptive names * cube_factor replaces srtt[scaled by count] / HZ * ((1 << (10+2*BICTCP_HZ)) / bic_scale) * beta_scale replaces 8*(BICTCP_BETA_SCALE+beta)/3/(BICTCP_BETA_SCALE-beta); Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03[TCP] BIC: CUBIC window growth (2.0)Stephen Hemminger1-0/+445
Replace existing BIC version 1.1 with new version 2.0. The main change is to replace the window growth function with a cubic function as described in: http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/cubic-paper.pdf Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.