Here is "year's" description of performance, i have not touched that part of the code and don't wanna add too much stuff to this mod so its gonna affect performance. Also i have never built mega bases, i keep my chest count pretty low, even 3k is way too much for my play style:
This mod is tuned to take about 1-3ms every tick and does a fixed amount of work on every tick. While this is a lot of time for each tick, this mod also does a lot of work to transport all items for an entire base. For larger bases this overhead is comparable to the render time for belts, trains and bots.
On the test world with 2048 network chests and 4096 loaders, the mod takes 2.5ms per tick which is about half the game update time on my computer.
Internally the mod maintains a FIFO queue of every Network Chest and Tank. On every tick it:
Pops 20 entities off the front of the queue, updates the entities, and pushes them to the back of the queue.
Randomly swaps a single entity to the front of the queue to slowly shuffle the update order.
Because this approach only scans a fixed number of chests per tick, chests will be scanned less frequently as the base scales up and more chests are built. It's sometimes necessary to increase the buffer and limit of high-throughput items like iron or copper and usually a buffer of 500-1000 items is enough to keep a full blue belt saturated.
Network chests have no trouble keeping blue belts saturated with less than 2K Network Chests in the map. However there have been reports that it is hard to saturate belts in larger factories with ~50K Network Chests. While improving mod performance is a key area of focus, in the short term it is currently recommended to keep the number of chests below 3K.
