From e29a8e0537c419aa0a612db39b0feb45148a8350 Mon Sep 17 00:00:00 2001 From: Anton Aksola Date: Tue, 20 Sep 2016 06:01:27 +0000 Subject: iproute2: build nsid-name cache only for commands that need it The calling of netns_map_init() before command parsing introduced a performance issue with large number of namespaces. As commands such as add, del and exec do not need to iterate through /var/run/netns it would be good not no build the cache before executing these commands. Example: unpatched: time seq 1 1000 | xargs -n 1 ip netns add real 0m16.832s user 0m1.350s sys 0m15.029s patched: time seq 1 1000 | xargs -n 1 ip netns add real 0m3.859s user 0m0.132s sys 0m3.205s Signed-off-by: Anton Aksola Acked-by: Nicolas Dichtel --- ip/ipnetns.c | 31 ++++++++++++++++++++++--------- 1 file changed, 22 insertions(+), 9 deletions(-) (limited to 'ip/ipnetns.c') diff --git a/ip/ipnetns.c b/ip/ipnetns.c index ccc652c1..bd1e9013 100644 --- a/ip/ipnetns.c +++ b/ip/ipnetns.c @@ -194,6 +194,18 @@ static void netns_map_del(struct nsid_cache *c) free(c); } +void netns_nsid_socket_init(void) +{ + if (rtnsh.fd > -1 || !ipnetns_have_nsid()) + return; + + if (rtnl_open(&rtnsh, 0) < 0) { + fprintf(stderr, "Cannot open rtnetlink\n"); + exit(1); + } + +} + void netns_map_init(void) { static int initialized; @@ -204,11 +216,6 @@ void netns_map_init(void) if (initialized || !ipnetns_have_nsid()) return; - if (rtnl_open(&rtnsh, 0) < 0) { - fprintf(stderr, "Cannot open rtnetlink\n"); - exit(1); - } - dir = opendir(NETNS_RUN_DIR); if (!dir) return; @@ -775,17 +782,23 @@ static int netns_monitor(int argc, char **argv) int do_netns(int argc, char **argv) { - netns_map_init(); + netns_nsid_socket_init(); - if (argc < 1) + if (argc < 1) { + netns_map_init(); return netns_list(0, NULL); + } if ((matches(*argv, "list") == 0) || (matches(*argv, "show") == 0) || - (matches(*argv, "lst") == 0)) + (matches(*argv, "lst") == 0)) { + netns_map_init(); return netns_list(argc-1, argv+1); + } - if ((matches(*argv, "list-id") == 0)) + if ((matches(*argv, "list-id") == 0)) { + netns_map_init(); return netns_list_id(argc-1, argv+1); + } if (matches(*argv, "help") == 0) return usage(); -- cgit v1.2.3