How many robots is too many?

[Yoda Nobunaga]

Okay, for reference, I have a mod installed called Factorio World which makes the map look like Earth. My ultimate goal is to get rid of all the biters on it and establish full Roboport coverage. The vanilla equivalent would be a huge island.

So I'm more or less pursuing megabase proportions, though I do have an upper limit. A constant problem I'm running into is that I never have enough robots to do the tasks I need so I keep adding more and I have a gut feeling that if I add too many I'll cause my game to lag and slow down.

So that's my question. How many robots can be in the network without tanking the game's performance?

[Xpain]

I have now close to 600 K bots.... it is getting slow when there is a lot of work to do.

[Crimson Tide]

I cant give you a number, but I would think its got to do with your specs and not truly a hardcount number within the game.

[Shurenai]

It's going to be down to your personal computer specs, and what you consider to be unplayable lag. Robots are fairly good for UPS when used properly, but can be a massive UPS hog when used improperly. FPS wise, there won't be much of a noticable effect when they aren't on screen, but being in the thick of their action can tank FPS considerably.

I would personally recommend against making a single massive robotic network as you're suggesting though- Even ignoring UPS/FPS lag, the simple fact is that as you build a bot network larger and larger, the response time of bots to a task gets larger and larger too. For example, if you build your storage system in the exact center, then if a task down in 'Florida' requires something from those chests, that bot has to fly alllllllll the way from wherever it started, to the storage system, and then alllllllll the way down to 'Florida' to fulfill the operation- And the many, many, MANY stops to recharge along the way.

Multiple smaller well-tuned networks is a much better option than one single monumental network for that reason.

[Hurkyl]

For construction, I think there's a practical limit of 600 or so, because the game simply won't assign more concurrent construction tasks than that? I suppose there's some marginal benefit to having more than 600 construction bots in the network, though, because it might mean there's more likely to be a bot near the task.

[PunCrathod]

Originally posted by Hurkyl:

For construction, I think there's a practical limit of 600 or so, because the game simply won't assign more concurrent construction tasks than that? I suppose there's some marginal benefit to having more than 600 construction bots in the network, though, because it might mean there's more likely to be a bot near the task.

That 600 limit is a misunderstanding. How the construction queue works is that each tick it will try to start the first item on the queue until one of the following variables is reached
max-failed-attempts-per-tick-per-construction-queue: default value 1
max-successful-attempts-per-tick-per-construction-queue: default value 5
If a job fails to start it will be put at the end of the queue and it will make an alert for that job that lasts for 600 ticks(10 seconds at 60ups).
And with default settings since it will stop after one failed attempt per tick you will only ever see 600 simultaneous alerts.
There is no limit to how many jobs can be active at the same time. Only the rate at which the jobs can be started is limited.

[knighttemplar1960]

Recharge time is one thing that can get in the way. Each roboport can handle the recharging needs of about 200-250 bots.