Author: Anand Buddhdev Date: To: exim-users Subject: Re: [Exim] pipelining in outbound SMTP ?
On Thu, Jan 20, 2000 at 08:29:28PM +0000, Nigel Metheringham wrote:
> > Is there any plan to add such code in? At least 3 well-known MTA's
> > support pipelining in the SMTP server (qmail, exim, postfix), but
> > only postfix and serialmail use it in their SMTP client, and so
> > the majority of SMTP transactions don't make use of this timesaving
> > feature.
>
> how much time does this actually save??
> I guess it may cut down overall latency, although cost a bit of CPU...
Someone on the postfix mailing list did some tests. They used a sample
message with more than one recipient, and sent it to a host, first to a
sendmail daemon (no pipelining), and then to a postfix daemon
(pipelining). The client was postfix. In the first instance, the message
took about 9 seconds to go through, in the second instance, it took just
2 seconds.
However, I'm going to try and do some of my own tests to see how much
difference pipelining makes. I'll try and post the results here.
