From mboxrd@z Thu Jan 1 00:00:00 1970 From: ebiederm@xmission.com (Eric W. Biederman) Subject: [RFC][PATCH] iproute: Faster ip link add, set and delete Date: Fri, 22 Mar 2013 15:23:14 -0700 Message-ID: <87k3ozm5v1.fsf@xmission.com> Mime-Version: 1.0 Content-Type: text/plain Cc: , Serge Hallyn , Benoit Lourdelet To: Stephen Hemminger Return-path: Received: from out02.mta.xmission.com ([166.70.13.232]:43642 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1423359Ab3CVWXY (ORCPT ); Fri, 22 Mar 2013 18:23:24 -0400 Sender: netdev-owner@vger.kernel.org List-ID: Because ip link add, set, and delete map the interface name to the interface index by dumping all of the interfaces before performing their respective commands. Operations that should be constant time slow down when lots of network interfaces are in use. Resulting in O(N^2) time to work with O(N) devices. Make the work that iproute does constant time by passing the interface name to the kernel instead. In small scale testing on my system this shows dramatic performance increases of ip link add from 120s to just 11s to add 5000 network devices. And from longer than I cared to wait to just 58s to delete all of those interfaces again. Cc: Serge Hallyn Reported-by: Benoit Lourdelet Signed-off-by: "Eric W. Biederman" --- I think I am bungling the case where people specify an ifindex as ifNNNN but does anyone care? ip/iplink.c | 19 +------------------ 1 files changed, 1 insertions(+), 18 deletions(-) diff --git a/ip/iplink.c b/ip/iplink.c index ad33611..6dffbf0 100644 --- a/ip/iplink.c +++ b/ip/iplink.c @@ -533,8 +533,6 @@ static int iplink_modify(int cmd, unsigned int flags, int argc, char **argv) } } - ll_init_map(&rth); - if (!(flags & NLM_F_CREATE)) { if (!dev) { fprintf(stderr, "Not enough information: \"dev\" " @@ -542,27 +540,12 @@ static int iplink_modify(int cmd, unsigned int flags, int argc, char **argv) exit(-1); } - req.i.ifi_index = ll_name_to_index(dev); - if (req.i.ifi_index == 0) { - fprintf(stderr, "Cannot find device \"%s\"\n", dev); - return -1; - } + name = dev; } else { /* Allow "ip link add dev" and "ip link add name" */ if (!name) name = dev; - if (link) { - int ifindex; - - ifindex = ll_name_to_index(link); - if (ifindex == 0) { - fprintf(stderr, "Cannot find device \"%s\"\n", - link); - return -1; - } - addattr_l(&req.n, sizeof(req), IFLA_LINK, &ifindex, 4); - } } if (name) { -- 1.7.5.4