Provide detailed server hosting advice

[LilithSilver]

We should provide tutorials and recommendations for setting up Backstitch servers. In particular, advice about Tailscale and Zerotier setup would be a good idea.

[tt-glossydon]

The public alpha test server was said to be a quad-core, eight-gigabyte system. Although specific components and their speeds aren't necessary, it might still be beneficial to give details in a more front-facing manner with regards to hosting a server.
Here's a short list of hardware/software considerations in no particular order:

• Processor specs, including clock and core count, and if lower-power processors can meet recommendation.
• Memory specs, including megatransfers and capacity, and memory consumption.
• Environment, including operating system and/or containers.
• Disk specs, including storage technology type and capacity, and if any file systems are better suited for Backstitch.

Something else to consider is contributor capacity. The public alpha test server was said to start reaching capacity at ten contributors. For a given system setup, at what point will users begin to feel the server start to fall behind? Does this account for multiple instances of Backstitch on the same set of hardware?

Although I'm sure people are in possession of ample processing power, it isn't often people have multiple machines handy. Would running Backstitch on their only machine create friction when working on Godot at the same time?

Internet connections are not made equal. What impact does Backstitch have on a network? When a user activates the proverbial monkey at a typewriter, what does usage look like?

Single-board computers are small, generally affordable, and can be power efficient. Are there brands which produce SBCs that have enough horsepower to drive a Backstitch server? Does this include ARM processors? Does this include RISC-V processors?

It was also said that a Raspberry Pi was not suitable for use as a server. What model of Raspberry Pi tested negatively, and what were the conditions it faced?

[LilithSilver]

Great questions. Most of these are unfortunately "unknown" -- this means we need to work on profiling the sync infrastructure, so that we can actually provide answers here.

A couple specific answers, though:

Although I'm sure people are in possession of ample processing power, it isn't often people have multiple machines handy. Would running Backstitch on their only machine create friction when working on Godot at the same time?

I haven't run into issues testing Backstitch on a single machine alongside a local sync server, with up to 3 local copies of Godot open, all syncing (on Threadbare). Feasibility of running side-by-side with Godot will of course change based on the requirements of your project, but syncing isn't that expensive.

It was also said that a Raspberry Pi was not suitable for use as a server. What model of Raspberry Pi tested negatively, and what were the conditions it faced?

This was more a ballpark estimate from me. I haven't tried it, actually. Maybe it runs fine?

A few things that may also change these answers:

• At some point in the coming months (ETA TBD), we'll additionally be switching to Subduction Sync, which should be much more efficient. In particular, it'll allow work from a single document to split across cores. (Currently, it's 1 document per core, so lots of contributors on a single branch could cause contention.)
• We plan on integrating an (optional) HTTP performance dashboard into the sync server. Should help us benchmark!

[tt-glossydon]

This was more a ballpark estimate from me. I haven't tried it, actually. Maybe it runs fine?

Both the Raspberry Pi 4 and Raspberry Pi 5 are quad-core systems. Clocks are in the gigahertz.
Memory for the Pi 5 goes at 4267 megahertz, and capacities exist from 1GB to 16GB.

I happen to have a Pi 5. The SoC can punch up with an intel N100 processor. The server I run is using a Celeron N4120 processor, which hasn't given me any issues so far. If I could hazard a guess, modern Raspberry Pis should be capable of running the server, granted they are running the server in the proper conditions.

I haven't run into issues testing Backstitch on a single machine alongside a local sync server, with up to 3 local copies of Godot open, all syncing (on Threadbare).

What are the rough specs for this setup? CPU cores, clocks, disk technology?

Outside of hardware related concerns, it's probable that users trying to connect to the server will inevitably run into some kind of issue in the setup or post-setup. It may also happen that the environment does not allow for things like MagicDNS to function, altering what can be placed in the address bar during setup.

If when connecting via Tailnet through Tailscale, the tailnet which the user connects to may be their own instead of the server's. This can happen, even if the devices are on the same LAN.

Small footnotes like these could exist per-tunneling method.

At some point in the coming months (ETA TBD), we'll additionally be switching to Subduction Sync, which should be much more efficient. In particular, it'll allow work from a single document to split across cores. (Currently, it's 1 document per core, so lots of contributors on a single branch could cause contention.)

If this is true, congestion could be reduced, and low-spec systems might be better able to handle more contributors on the same branch.

Even still, understanding the current behavior better informs server hosts how equipped their hardware is to reliably run Backstitch.
Thanks for sharing!

[LilithSilver]

What are the rough specs for this setup? CPU cores, clocks, disk technology?

SSD, Radeon 5800x3D

Also cool, I didn't realize rasbpi had gotten so fast. I still use the little potatoes from 2015!

Mdns should work fine, and we should instruct users to use it -- if it doesn't we had better take it up with our network library haha.