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
| ||
|
Date: Thu, 28 Mar 2013 17:25:46 -0700 From: ebiederm@...ssion.com (Eric W. Biederman) To: Eric Dumazet <eric.dumazet@...il.com> Cc: Stephen Hemminger <stephen@...workplumber.org>, Benoit Lourdelet <blourdel@...iper.net>, Serge Hallyn <serge.hallyn@...ntu.com>, "netdev\@vger.kernel.org" <netdev@...r.kernel.org> Subject: Re: [RFC][PATCH] iproute: Faster ip link add, set and delete Eric Dumazet <eric.dumazet@...il.com> writes: > On Thu, 2013-03-28 at 16:52 -0700, Eric W. Biederman wrote: > >> On my microbenchmark of just creating 5000 veth pairs this takes pairs >> 16s instead of 13s of my earlier hacks but that is well down in the >> usable range. > > I guess most of the time is taken by sysctl_check_table() All of the significant sysctl slowdowns were fixed in 3.4. If you see something of sysctl show up in a trace I would be happy to talk about it. The kernel side seems to be creating N network devices seems to take NlogN time now. Both sysfs and sysctl store directories as rbtrees removing their previous bottlenecks. The loop I timed at 16s was just: time for i in $(seq 1 5000) ; do ip link add a$i type veth peer name b$i; done There is plenty of room for inefficiencies in 10000 network devices and 5000 forks+execs. Eric -- 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
Powered by blists - more mailing lists