I’ve got a few questions about the performance cost of using multiple connections.
As stated at https://docs.syncthing.net/users/tuning.html#tuning-for-low-resources, when tuning for low resources, the recommendation is as follows.
Set to 1 to reduce the amount of overhead per device, as each connection has a memory and CPU cost.
I’m testing a large number of connections right now, and with just two devices connected to one another, and the difference in RAM usage between the default of 3 connections and the maximum of 128 connections is barely 15 MB.
Is this really it? Obviously, if the number of remote devices is high and all of them use this many connections, the overall RAM cost may be a few hundred MBs, but still, this doesn’t seem like a lot.
I’m also curious about the potential CPU cost. How low-end the device needs to be for it to actually make a difference? For instance, my slowest device has Intel Atom Z3740 as its CPU, and it seems to work with the default 3 connections just fine.