forked from luck/tmp_suning_uos_patched
0ccfe61803
On systems with a very large amount of memory, the heuristics in alloc_large_system_hash() result in a very large TCP established hash table: 16 millions of entries for a 128 GB ia64 system. This makes reading from /proc/net/tcp pretty slow (well over a second) and as a result netstat is slow on these machines. I know that /proc/net/tcp is deprecated in favor of tcp_diag, however at the moment netstat only knows of the former. I am skeptical that such a large TCP established hash is often needed. Just because a system has a lot of memory doesn't imply that it will have several millions of concurrent TCP connections. Thus I believe that we should put an arbitrary high limit to the size of the TCP established hash by default. Users who really need a bigger hash can always use the thash_entries boot parameter to get more. I propose 2 millions of entries as the arbitrary high limit. This makes /proc/net/tcp reasonably fast on the system in question (0.2 s) while being still large enough for me to be confident that network performance won't suffer. This is just one way to limit the hash size, there are others; I am not familiar enough with the TCP code to decide which is best. Thus, I would welcome the proposals of alternatives. [ 2 million is still too large, thus I've modified the limit in the change to be '512 * 1024'. -DaveM ] Signed-off-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: David S. Miller <davem@davemloft.net> |
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| .. | ||
| ipvs | ||
| netfilter | ||
| af_inet.c | ||
| ah4.c | ||
| arp.c | ||
| cipso_ipv4.c | ||
| datagram.c | ||
| devinet.c | ||
| esp4.c | ||
| fib_frontend.c | ||
| fib_hash.c | ||
| fib_lookup.h | ||
| fib_rules.c | ||
| fib_semantics.c | ||
| fib_trie.c | ||
| icmp.c | ||
| igmp.c | ||
| inet_connection_sock.c | ||
| inet_diag.c | ||
| inet_fragment.c | ||
| inet_hashtables.c | ||
| inet_lro.c | ||
| inet_timewait_sock.c | ||
| inetpeer.c | ||
| ip_forward.c | ||
| ip_fragment.c | ||
| ip_gre.c | ||
| ip_input.c | ||
| ip_options.c | ||
| ip_output.c | ||
| ip_sockglue.c | ||
| ipcomp.c | ||
| ipconfig.c | ||
| ipip.c | ||
| ipmr.c | ||
| Kconfig | ||
| Makefile | ||
| netfilter.c | ||
| proc.c | ||
| protocol.c | ||
| raw.c | ||
| route.c | ||
| syncookies.c | ||
| sysctl_net_ipv4.c | ||
| tcp_bic.c | ||
| tcp_cong.c | ||
| tcp_cubic.c | ||
| tcp_diag.c | ||
| tcp_highspeed.c | ||
| tcp_htcp.c | ||
| tcp_hybla.c | ||
| tcp_illinois.c | ||
| tcp_input.c | ||
| tcp_ipv4.c | ||
| tcp_lp.c | ||
| tcp_minisocks.c | ||
| tcp_output.c | ||
| tcp_probe.c | ||
| tcp_scalable.c | ||
| tcp_timer.c | ||
| tcp_vegas.c | ||
| tcp_vegas.h | ||
| tcp_veno.c | ||
| tcp_westwood.c | ||
| tcp_yeah.c | ||
| tcp.c | ||
| tunnel4.c | ||
| udp_impl.h | ||
| udp.c | ||
| udplite.c | ||
| xfrm4_input.c | ||
| xfrm4_mode_beet.c | ||
| xfrm4_mode_transport.c | ||
| xfrm4_mode_tunnel.c | ||
| xfrm4_output.c | ||
| xfrm4_policy.c | ||
| xfrm4_state.c | ||
| xfrm4_tunnel.c | ||