Re: [PATCH 2/2] send-email: supply a --send-delay=1 by default

From: brian m. carlson <sandals@crustytoothpaste.net>
Date: Mar 25, 2018, 21:01 UTC
Message-ID: <20180325210132.GE74743@genre.crustytoothpaste.net>
In-Reply-To: <20180325182803.30036-3-avarab@gmail.com>

On Sun, Mar 25, 2018 at 06:28:03PM +0000, Ævar Arnfjörð Bjarmason wrote:

Show 25 quoted lines

> The earlier change to add this option described the problem this
> option is trying to solve.
> 
> This turns it on by default with a value of 1 second, which'll
> hopefully solve it, and if not user reports as well as the
> X-Mailer-Send-Delay header should help debug it.
> 
> I think the trade-off of slowing down E-Mail sending to turn this on
> makes sense because:
> 
>  * GMail is a really common client, git.git's own unique authors by
>    %aE are ~30% @gmail.com, ~20% for linux.git. That's just patch
>    submitters, my guess is this it's much more common among those who
>    mostly read the list, and those users who aren't using mu4e / mutt
>    etc. anyway.
> 
>  * There's really no point in having this feature at all if it's not
>    made the default, since the entire point is to be able to read a
>    list like the git ML or the LKML and have patches from others show
>    up in order.
> 
>  * I don't think anyone's really sensitive to the sending part of
>    send-email taking longer. You just choose "all" and then switch to
>    another terminal while it does its thing if you have a huge series,
>    and for 1-3 patches I doubt anyone would notice this anyway.

I'm not sure that this is going to have the effect you want it to have. Let me give an example to demonstrate why.

If I send a series to the list, in order for this to work, you need my SMTP server (Postfix) to essentially send mails slowly enough to vger.kernel.org (ZMailer) that it doesn't batch them when it sends them to GMail. The problem is that with my mail server, due to filtering and such, already takes at least a second to accept, process, and relay submitted messages. vger still batched them and delivered them back to me out of order. This will be even worse with large series.

You are also assuming that my mail server will not have batched them and delivered them out of order, which it might well do, since Postfix uses a connection cache to machines that don't do STARTTLS (which, much to my annoyance, vger doesn't offer).

In short, I don't think this is going to be especially helpful because it won't change the status quo for a lot of senders. You'd have to insert some significant delay in order to get the effect you desire, and even then things could still be delivered out of order.

-- 
brian m. carlson / brian with sandals: Houston, Texas, US
https://www.crustytoothpaste.net/~bmc | My opinion only
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