Re: [Fwd: [Fwd: Is sendfile all that sexy? (fwd)]]

[dean gaudet]

huh -- i think with this apache could solve the problem documented in
heidemann's paper while also leaving nagle on... which would solve the CGI
dribbler vs. bulk problem i just posted about.

at the end of a request apache would check first if it can get another
request without blocking; if it would block then it issues a SIOCPUSH and
drops into poll() waiting for a new request.

this means the final packet of a response isn't ever delayed (which is the
motivation for turning off nagle); and a multi-request pipeline has
maximal packets... and a dribbling CGI won't cause as many tiny packets.

this may in fact also eliminate the need for CORK, unless anyone can
really think of an app that wouldn't even want small packets on the wire
when the server hasn't sent anything for a while.

i like this one :)

-dean

On Thu, 18 Jan 2001, Andrea Arcangeli wrote:

> diff -urN -X /home/andrea/bin/dontdiff 2.4.1pre8/net/ipv4/tcp.c SIOCPUSH/net/ipv4/tcp.c
> --- 2.4.1pre8/net/ipv4/tcp.c	Wed Jan 17 04:02:38 2001
> +++ SIOCPUSH/net/ipv4/tcp.c	Thu Jan 18 19:10:14 2001
> @@ -671,6 +671,11 @@
>  		else
>  			answ = tp->write_seq - tp->snd_una;
>  		break;
> +	case SIOCPUSH:
> +		lock_sock(sk);
> +		__tcp_push_pending_frames(sk, tp, tcp_current_mss(sk), 1);
> +		release_sock(sk);
> +		break;
>  	default:
>  		return(-ENOIOCTLCMD);
>  	};