Some timing info on populating mailboxes

[Wesley Craig]

On 17 Dec 2006, at 02:22, Ross Boylan wrote:
> An earlier report on this list said
> sysctl -w net.inet.tcp.delayed_ack=0
> worked wonders.  There does not seem to be such a setting in my Linux
> 2.6.18 kernel.

I don't recall if Linux has ever had that sysctl.  Mac OS X does.   
This option globally disables Nagel's Algorithm.  You can also  
disable it on a per-socket basis:

	int zero = 0;

         if (( proto = getprotobyname( "tcp" )) == NULL ) {
             syslog( LOG_ERR, "getprotobyname: %m" );
             return( -1 );
         }

         if ( setsockopt( socket_fd, proto->p_proto, TCP_NODELAY,  
&zero, sizeof( zero )) != 0 ) {
             syslog( LOG_ERR, "snet_setopt: %m" );
             return( -1 );
         }

For protocols (or implementations of protocols in the case of IMAP)  
with a lot of small back & forth chatter, it does in fact do wonders.

:wes