From f86dcc5aa8c7908f2c287e7a211228df599e3e71 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 7 Oct 2009 00:37:59 +0000 Subject: udp: dynamically size hash tables at boot time UDP_HTABLE_SIZE was initialy defined to 128, which is a bit small for several setups. 4000 active UDP sockets -> 32 sockets per chain in average. An incoming frame has to lookup all sockets to find best match, so long chains hurt latency. Instead of a fixed size hash table that cant be perfect for every needs, let UDP stack choose its table size at boot time like tcp/ip route, using alloc_large_system_hash() helper Add an optional boot parameter, uhash_entries=x so that an admin can force a size between 256 and 65536 if needed, like thash_entries and rhash_entries. dmesg logs two new lines : [ 0.647039] UDP hash table entries: 512 (order: 0, 4096 bytes) [ 0.647099] UDP Lite hash table entries: 512 (order: 0, 4096 bytes) Maximal size on 64bit arches would be 65536 slots, ie 1 MBytes for non debugging spinlocks. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv4/udplite.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net/ipv4/udplite.c') diff --git a/net/ipv4/udplite.c b/net/ipv4/udplite.c index 95248d7f75ec..470c504b9554 100644 --- a/net/ipv4/udplite.c +++ b/net/ipv4/udplite.c @@ -12,7 +12,7 @@ */ #include "udp_impl.h" -struct udp_table udplite_table; +struct udp_table udplite_table __read_mostly; EXPORT_SYMBOL(udplite_table); static int udplite_rcv(struct sk_buff *skb) @@ -110,7 +110,7 @@ static inline int udplite4_proc_init(void) void __init udplite4_register(void) { - udp_table_init(&udplite_table); + udp_table_init(&udplite_table, "UDP-Lite"); if (proto_register(&udplite_prot, 1)) goto out_register_err; -- cgit v1.2.3-70-g09d2