tcp: change default tcp hash size

As time passed, available memory increased faster than number of
concurrent tcp sockets.

As a result, a machine with 4GB of ram gets a hash table
with 524288 slots, using 8388608 bytes of memory.

Lets change that by a 16x factor (one slot for 128 KB of ram)

Even if a small machine needs a _lot_ of sockets, tcp lookups are now
very efficient, using one cache line per socket.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2012-11-30 10:08:52 +00:00 committed by David S. Miller
parent abe303dbc2
commit fd90b29d75

View file

@ -3590,8 +3590,7 @@ void __init tcp_init(void)
alloc_large_system_hash("TCP established",
sizeof(struct inet_ehash_bucket),
thash_entries,
(totalram_pages >= 128 * 1024) ?
13 : 15,
17, /* one slot per 128 KB of memory */
0,
NULL,
&tcp_hashinfo.ehash_mask,
@ -3607,8 +3606,7 @@ void __init tcp_init(void)
alloc_large_system_hash("TCP bind",
sizeof(struct inet_bind_hashbucket),
tcp_hashinfo.ehash_mask + 1,
(totalram_pages >= 128 * 1024) ?
13 : 15,
17, /* one slot per 128 KB of memory */
0,
&tcp_hashinfo.bhash_size,
NULL,