Le Wednesday 27 Feb 2013 à 15:05:47 (+0100), Stefan Hajnoczi a écrit :
> Reduce -netdev socket latency by disabling the Nagle algorithm on
> SOCK_STREAM sockets in net/socket.c. Since we are tunelling Ethernet
> over TCP we shouldn't artificially delay outgoing packets, let the guest
> decide packet scheduling.
>
> I already get sub-millisecond -netdev socket ping times on localhost, so
> there was no measurable difference in my testing. This won't hurt
> though and may improve remote socket performance.
>
> Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
> ---
> net/socket.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/net/socket.c b/net/socket.c
> index 396dc8c..c0dcc31 100644
> --- a/net/socket.c
> +++ b/net/socket.c
> @@ -439,6 +439,9 @@ static NetSocketState
> *net_socket_fd_init_stream(NetClientState *peer,
> s->fd = fd;
> s->listen_fd = -1;
>
> + /* Disable Nagle algorithm on TCP sockets to reduce latency */
> + socket_set_nodelay(fd);
> +
> if (is_connected) {
> net_socket_connect(s);
> } else {
> --
> 1.8.1.2
>
>
Reviewed-by: Benoit Canet <ben...@irqsave.net>
