On Fri, Feb 12, 2021 at 09:13:58PM +1000, Mark Constable wrote:
> The reason for wanting this setup is that I've started using delta.chat
> with a few friends and I want to maximize the speed between our mailservers
> and also try to minimize the size of the messages to sometimes <1500 bytes.
Message content is sent via TCP as a series of back to back packets, and
so long as the TCP window is wide enough to accomodate the bandwidth*delay
product, there is no reason to try to squeeze the message into a single
IP packet. Latency is not improved.
> FWIW disabling DKIM seems to make the biggest difference...
Disabling DKIM checks eliminates DNS lookups for the requisite keys.
> and why not SPF while we're at it...
Also eliminates DNS lookups.
> Is there any other magic I could use in this peer-to-peer scenario to reduce
> the number of unnecessary headers during transit on a per domain basis?
Waste of time. The cost of a few additioanl headers is irrelevant. Pay
attention to network round-trips, not payload sizes.
--
Viktor.
