Em Thu, Jan 31, 2008 at 08:57:53PM +0100, Eric Dumazet escreveu:
> Arnaldo Carvalho de Melo a écrit :
>> /home/acme/git/net-2.6/net/ipv6/tcp_ipv6.c:
>> struct tcp_sock | -16
>> struct tcp6_sock | -16
>> 2 structs changed
>>
>> Now it is at:
>>
>> /* size: 1552, cachelines: 25 */
>> /* paddings: 2, sum paddings: 8 */
>> /* last cacheline: 16 bytes */
>>
>> As soon as we stop using skb_queue_list we'll get it down to 24 cachelines.
>>
>> Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
>> ---
>> include/linux/tcp.h | 6 ++++--
>> 1 files changed, 4 insertions(+), 2 deletions(-)
>>
>> diff --git a/include/linux/tcp.h b/include/linux/tcp.h
>> index 08027f1..f48644d 100644
>> --- a/include/linux/tcp.h
>> +++ b/include/linux/tcp.h
>> @@ -304,7 +304,6 @@ struct tcp_sock {
>> u32 rtt_seq; /* sequence number to update rttvar */
>> u32 packets_out; /* Packets which are "in flight" */
>> - u32 retrans_out; /* Retransmitted packets out */
>> /*
>> * Options received (usually on last packet, some only on SYN packets).
>> */
>> @@ -332,6 +331,8 @@ struct tcp_sock {
>> struct tcp_sack_block recv_sack_cache[4];
>> + u32 retrans_out; /* Retransmitted packets out */
>> +
>
> Hum... retrans_out should sit close to packets_out (or lost_out/sacked_out
> ???), please.
>
> 'struct tcp_sock' is very large on 64 bits, so I would prefer to make sure
> most paths dont need to touch all 24 cache lines (or 25 cache lines).
That is perfectly fine, I'll replace my patch with another, that states
this beyond doubt.
- Arnaldo
-
To unsubscribe from this list: send the line "unsubscribe dccp" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
