kpriv/linux-hardened
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

RDS-TCP: Do not bloat sndbuf/rcvbuf in rds_tcp_tune

Browse source 
Using the value of RDS_TCP_DEFAULT_BUFSIZE (128K)
clobbers efficient use of TSO because it inflates the size_goal
that is computed in tcp_sendmsg/tcp_sendpage and skews packet
latency, and the default values for these parameters actually
results in significantly better performance.

In request-response tests using rds-stress with a packet size of
100K with 16 threads (test parameters -q 100000 -a 256 -t16 -d16)
between a single pair of IP addresses achieves a throughput of
6-8 Gbps. Without this patch, throughput maxes at 2-3 Gbps under
equivalent conditions on these platforms.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Sowmini Varadhan 2015-09-30 16:54:08 -04:00 committed by David S. Miller
parent 3b20fc3897
commit 1edd6a14d2
1 changed files with 4 additions and 12 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

16
net/rds/tcp.c
View file

@ -67,21 +67,13 @@ void rds_tcp_nonagle(struct socket *sock)
set_fs(oldfs);
}
/* All module specific customizations to the RDS-TCP socket should be done in
* rds_tcp_tune() and applied after socket creation. In general these
* customizations should be tunable via module_param()
*/
void rds_tcp_tune(struct socket *sock)
{
struct sock *sk = sock->sk;
rds_tcp_nonagle(sock);
/*
* We're trying to saturate gigabit with the default,
* see svc_sock_setbufsize().
*/
lock_sock(sk);
sk->sk_sndbuf = RDS_TCP_DEFAULT_BUFSIZE;
sk->sk_rcvbuf = RDS_TCP_DEFAULT_BUFSIZE;
sk->sk_userlocks |= SOCK_SNDBUF_LOCK|SOCK_RCVBUF_LOCK;
release_sock(sk);
}
u32 rds_tcp_snd_nxt(struct rds_tcp_connection *tc)