[PATCH v2 net-next 2/3] RDS-TCP: Do not bloat sndbuf/rcvbuf in rds_tcp_tune
From: Sowmini Varadhan <hidden>
Date: 2015-09-30 20:54:36
Also in:
lkml
Subsystem:
networking [general], rds - reliable datagram sockets, the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Allison Henderson, Linus Torvalds
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 <redacted> --- net/rds/tcp.c | 16 ++++------------ 1 files changed, 4 insertions(+), 12 deletions(-)
diff --git a/net/rds/tcp.c b/net/rds/tcp.c
index c42b60b..9d6ddba 100644
--- a/net/rds/tcp.c
+++ b/net/rds/tcp.c@@ -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)
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1.7.1