Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758553Ab2EYUQt (ORCPT ); Fri, 25 May 2012 16:16:49 -0400 Received: from intmgw001.ash2.facebook.com ([66.220.155.178]:62860 "EHLO intmgw002.ash2.facebook.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1756085Ab2EYUQr (ORCPT ); Fri, 25 May 2012 16:16:47 -0400 From: Arun Sharma To: netdev@vger.kernel.org Cc: Arun Sharma , linux-kernel@vger.kernel.org, David Miller Subject: [PATCH] net: compute a more reasonable default ip6_rt_max_size Date: Fri, 25 May 2012 13:15:34 -0700 Message-Id: <1337976934-18065-1-git-send-email-asharma@fb.com> X-Mailer: git-send-email 1.7.8.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2262 Lines: 85 The algorithm is based on ipv4 and alloc_large_system_hash(). The following data is from a x86_64 box I tested: 128MB $ cat /proc/sys/net/ipv{4,6}/route/max_size 16384 22444 512MB $ cat /proc/sys/net/ipv{4,6}/route/max_size 65536 99856 1GB $ cat /proc/sys/net/ipv{4,6}/route/max_size 524288 203068 2GB $ cat /proc/sys/net/ipv{4,6}/route/max_size 1048576 524288 4GB $ cat /proc/sys/net/ipv{4,6}/route/max_size 2097152 524288 Signed-off-by: Arun Sharma Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: David Miller --- net/ipv6/route.c | 21 ++++++++++++++++++++- 1 files changed, 20 insertions(+), 1 deletions(-) diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 49d6ce1..c89ebbb 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -2827,6 +2827,16 @@ struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net) } #endif +static __initdata unsigned long ip6_rt_entries; +static int __init set_rt_entries(char *str) +{ + if (!str) + return 0; + ip6_rt_entries = simple_strtoul(str, &str, 0); + return 1; +} +__setup("ip6_rt_entries=", set_rt_entries); + static int __net_init ip6_route_net_init(struct net *net) { int ret = -ENOMEM; @@ -2872,8 +2882,17 @@ static int __net_init ip6_route_net_init(struct net *net) ip6_template_metrics, true); #endif + /* Compute a reasonable default based on what we do for ipv4 + * total size = 1/16th of total RAM + * No more than 512k entries unless overridden on kernel cmdline */ + if (ip6_rt_entries == 0) { + ip6_rt_entries = (totalram_pages << PAGE_SHIFT) >> 4; + ip6_rt_entries /= sizeof(struct rt6_info); + ip6_rt_entries = min(512 * 1024UL, ip6_rt_entries); + } + net->ipv6.sysctl.flush_delay = 0; - net->ipv6.sysctl.ip6_rt_max_size = 4096; + net->ipv6.sysctl.ip6_rt_max_size = ip6_rt_entries; net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2; net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ; net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ; -- 1.7.8.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/