Re: Fastest way to inject a lot of mail?

According to Grant Taylor  <gtaylor@tnetconsulting.net>:

On 3/8/24 18:25, John Levine wrote:

So here's a question: I have on the order of 10,000 messages, each with a dozen or so recipients.

>
That's quite a few discrete messages.
>

It currently takes about 6 hours on a moderately fast VPS.

>
Rough math, that's a little over 2 seconds per message.
>
On one hand that seems a little slow, but on the other hand, maybe not.
>
How big are the messages?  There's a big difference if it's a few kB of text vs multiple MB of attachments.

Not large, plain text, maybe 10K.

If it's Linux, `iostat -x 1` or `sar` or `nmon` are good candidates.
>
I don't remember, are there any milters in Sendmail?

Not on this machine.

What are you using for the DNS server?  Is it local to the system or are you dependent on something across the network.  If it's across the network, how far across the network is it?

I'll have to check but I believe there's a local cache on the LAN.  It's
sending it all to a smarthost so I wouldn't expect a lot of DNS traffic.

Are there any errors in any logs?

No, it all works, just not terribly fast.

I would naively think that Sendmail itself could handle messages quite a bit faster.  But I'm probably thinking about SMTP interface vs command line forking.

Right. Hey, here's a question: if I injected the mail via SMTP to
127.0.0.1, would that be faster than forking and running sendmail?
Slower? Or am I the first person in sendmail's 35 year history to ask
this question?
--
Regards,
John Levine, johnl@taugh.com, Primary Perpetrator of "The Internet for Dummies",
Please consider the environment before reading this e-mail. https://jl.ly