From: Kirill Korotaev Date: Tue, 8 Aug 2006 03:44:22 +0000 (-0700) Subject: [IPV4]: Limit rt cache size properly. X-Git-Tag: v2.6.18-rc5~121^2~7 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8d1502de27c46b365b5c86e17d173083d3d6c9ac;p=linux-2.6 [IPV4]: Limit rt cache size properly. From: Kirill Korotaev During OpenVZ stress testing we found that UDP traffic with random src can generate too much excessive rt hash growing leading finally to OOM and kernel panics. It was found that for 4GB i686 system (having 1048576 total pages and 225280 normal zone pages) kernel allocates the following route hash: syslog: IP route cache hash table entries: 262144 (order: 8, 1048576 bytes) => ip_rt_max_size = 4194304 entries, i.e. max rt size is 4194304 * 256b = 1Gb of RAM > normal_zone Attached the patch which removes HASH_HIGHMEM flag from alloc_large_system_hash() call. Signed-off-by: David S. Miller --- diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 19bd49d69d..b873cbcdd0 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -3157,7 +3157,7 @@ int __init ip_rt_init(void) rhash_entries, (num_physpages >= 128 * 1024) ? 15 : 17, - HASH_HIGHMEM, + 0, &rt_hash_log, &rt_hash_mask, 0);