| Message ID | 20081030083641.55e936b0@extreme |
|---|---|
| State | Rejected, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Stephen Hemminger <shemminger@vyatta.com> Date: Thu, 30 Oct 2008 08:36:41 -0700 > Change the configuration defaults to mark BIC as experimental. > BIC is too aggressive and was replaced by CUBIC. Debian was picking > BIC in their default config (should be fixed by now), but the configuration > documentation did not make it explicit that this was a bad idea. > > Also update the URLs in the configuration documentation to current > locations. > > Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> I understand your intention, but I'm not so sure we should do this. It's more than a double standard to make this change, yet still allow things like HTCP to still be a default. And you can't even make this selection without asking for TCP_CONG_ADVANCED. Well... duh! -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, 31 Oct 2008 00:50:33 -0700 (PDT) David Miller <davem@davemloft.net> wrote: > From: Stephen Hemminger <shemminger@vyatta.com> > Date: Thu, 30 Oct 2008 08:36:41 -0700 > > > Change the configuration defaults to mark BIC as experimental. > > BIC is too aggressive and was replaced by CUBIC. Debian was picking > > BIC in their default config (should be fixed by now), but the configuration > > documentation did not make it explicit that this was a bad idea. > > > > Also update the URLs in the configuration documentation to current > > locations. > > > > Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> > > I understand your intention, but I'm not so sure we should do this. > > It's more than a double standard to make this change, yet still > allow things like HTCP to still be a default. > > And you can't even make this selection without asking for > TCP_CONG_ADVANCED. Well... duh! Some architectures were setting TCP_CONG_ADVANCED and choosing BIC arch/arm/configs/at91rm9200dk_defconfig:CONFIG_TCP_CONG_BIC=y arch/arm/configs/at91rm9200ek_defconfig:CONFIG_TCP_CONG_BIC=y arch/arm/configs/ateb9200_defconfig:CONFIG_TCP_CONG_BIC=y arch/arm/configs/collie_defconfig:CONFIG_TCP_CONG_BIC=y arch/arm/configs/kafa_defconfig:CONFIG_TCP_CONG_BIC=y arch/arm/configs/kb9202_defconfig:CONFIG_TCP_CONG_BIC=y arch/arm/configs/ks8695_defconfig:CONFIG_TCP_CONG_BIC=y arch/arm/configs/lpd7a404_defconfig:CONFIG_TCP_CONG_BIC=y arch/arm/configs/netx_defconfig:CONFIG_TCP_CONG_BIC=y arch/arm/configs/pnx4008_defconfig:CONFIG_TCP_CONG_BIC=y arch/arm/configs/realview_defconfig:CONFIG_TCP_CONG_BIC=y arch/arm/configs/versatile_defconfig:CONFIG_TCP_CONG_BIC=y arch/ia64/configs/bigsur_defconfig:CONFIG_TCP_CONG_BIC=y arch/ia64/configs/gensparse_defconfig:CONFIG_TCP_CONG_BIC=y arch/ia64/configs/sim_defconfig:CONFIG_TCP_CONG_BIC=y arch/mips/configs/bcm47xx_defconfig:CONFIG_TCP_CONG_BIC=y arch/mips/configs/rb532_defconfig:CONFIG_TCP_CONG_BIC=m arch/mips/configs/tb0287_defconfig:CONFIG_TCP_CONG_BIC=y arch/powerpc/configs/ppc6xx_defconfig:CONFIG_TCP_CONG_BIC=m -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Stephen Hemminger <shemminger@vyatta.com> Date: Fri, 31 Oct 2008 09:41:13 -0700 > On Fri, 31 Oct 2008 00:50:33 -0700 (PDT) > David Miller <davem@davemloft.net> wrote: > > > From: Stephen Hemminger <shemminger@vyatta.com> > > Date: Thu, 30 Oct 2008 08:36:41 -0700 > > > > > Change the configuration defaults to mark BIC as experimental. > > > BIC is too aggressive and was replaced by CUBIC. Debian was picking > > > BIC in their default config (should be fixed by now), but the configuration > > > documentation did not make it explicit that this was a bad idea. > > > > > > Also update the URLs in the configuration documentation to current > > > locations. > > > > > > Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> > > > > I understand your intention, but I'm not so sure we should do this. > > > > It's more than a double standard to make this change, yet still > > allow things like HTCP to still be a default. > > > > And you can't even make this selection without asking for > > TCP_CONG_ADVANCED. Well... duh! > > Some architectures were setting TCP_CONG_ADVANCED and choosing BIC I'm sure you can find a pile of other nonsense settings in the arch defconfigs if you keep looking. And those should be similarly fixed, but in the arch defconfigs. But that has no bearing on what we're discussing here. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
--- a/net/ipv4/Kconfig 2008-10-29 14:58:40.000000000 -0700 +++ b/net/ipv4/Kconfig 2008-10-30 08:18:08.000000000 -0700 @@ -437,7 +437,8 @@ if TCP_CONG_ADVANCED config TCP_CONG_BIC tristate "Binary Increase Congestion (BIC) control" - default m + depends on EXPERIMENTAL + default n ---help--- BIC-TCP is a sender-side only change that ensures a linear RTT fairness under large windows while offering both scalability and @@ -447,15 +448,24 @@ config TCP_CONG_BIC increment ensures linear RTT fairness as well as good scalability. Under small congestion windows, binary search increase provides TCP friendliness. - See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/ + + BIC growth function is too aggressive and should not be used + except for testing and comparision, use CUBIC instead. + + For further details see: + http://netsrv.csc.ncsu.edu/twiki/bin/view/Main/BIC config TCP_CONG_CUBIC tristate "CUBIC TCP" default y ---help--- - This is version 2.0 of BIC-TCP which uses a cubic growth function - among other techniques. - See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/cubic-paper.pdf + CUBIC TCP is an sender-side only modification to the congestion control + algothrim improved versions on the growth function of BIC and has an + improved slow start algoritm, called HyStart. + + For further details see: + http://netsrv.csc.ncsu.edu/twiki/bin/view/Main/BIC + config TCP_CONG_WESTWOOD tristate "TCP Westwood+" @@ -581,9 +591,6 @@ choice Select the TCP congestion control that will be used by default for all connections. - config DEFAULT_BIC - bool "Bic" if TCP_CONG_BIC=y - config DEFAULT_CUBIC bool "Cubic" if TCP_CONG_CUBIC=y @@ -610,7 +617,6 @@ config TCP_CONG_CUBIC config DEFAULT_TCP_CONG string - default "bic" if DEFAULT_BIC default "cubic" if DEFAULT_CUBIC default "htcp" if DEFAULT_HTCP default "vegas" if DEFAULT_VEGAS
Change the configuration defaults to mark BIC as experimental. BIC is too aggressive and was replaced by CUBIC. Debian was picking BIC in their default config (should be fixed by now), but the configuration documentation did not make it explicit that this was a bad idea. Also update the URLs in the configuration documentation to current locations. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html