netdev - Re: About disabling congestion control

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Fri, 07 Jan 2011 11:33:44 +0100
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	Syed Obaid Amin <obaidasyed@...il.com>
Cc:	Stephen Hemminger <shemminger@...tta.com>, netdev@...r.kernel.org,
	Michael Kerrisk <mtk.manpages@...il.com>
Subject: Re: About disabling congestion control

Le vendredi 07 janvier 2011 à 05:04 -0500, Syed Obaid Amin a écrit :
> Thanks for the reply. Yes I also thought to create a sort of NULL
> congestion control type that does nothing. But this way the changes
> would be system wide. BTW, would some one share the insight that why
> linux uses sysctl to select a congestion control algorithm instead of
> socket options.

Hmm, maybe "man 7 tcp" is not up2date.

It mentions TCP_CONGESTION once but doesnt describe it.

CC Michael Kerrisk <mtk.manpages@...il.com> ;)

http://www.kernel.org/doc/man-pages/online/pages/man7/tcp.7.html


Lets say you have a kernel with support for two congestion controls :

# cat /proc/sys/net/ipv4/tcp_allowed_congestion_control
cubic reno
# cat /proc/sys/net/ipv4/tcp_congestion_control
cubic


Therefore, default is cubic, but you can change to reno if you want.


setsockopt(sock, SOL_TCP, TCP_CONGESTION, "reno", strlen("reno"));



--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html