Bags To Riches

The small handmade backpack provides 12 slots & can be crafted for 50 cloth and five sewing kits at a T1 workbench. It is a default blueprint and will take 30 seconds to craft.

As mentioned in our start of the year blog post, memory usage is a key area of concern this year. One aspect I’ve been looking at lately is entity counts. Anything that gets networked in a Rust server is an entity, so every tree, building block, player, vehicle, etc. What might seem counterintuitive is that many Items in your inventory are also entities, specifically an entity we call a Planner. This is the blue sheet your player visually equips when they are deploying something (eg. a sleeping bag). Any Item that can be deployed in your inventory will have a corresponding Planner entity. This entity is created when the item is created, and will exist on the server (typically in the players hands or at the world origin if they are in a container) until that item is used or destroyed. We need this entity as it handles all the logistics of spawning the deployed version of the item.

To illustrate how many entities this creates we looked a list of entities on Facepunch EU2 towards the end of the November wipe last year. Out of 362,299 entities, 32,455 of them were Planners and are the largest count of entity (the next largest was Walls at 26,015). Since Planners are technically only needed when the player has the item equipped on their belt, this is a big waste of memory and processing time as well as needlessly bloating server save files. 

This month we’ve rolled out a change that will only spawn a Planner for these Items once the Item is in a players inventory, then delete the entity when it is moved back into an inventory. This should dramatically cut down on the number of entities taking up memory for no real reason. 

We also applied this change to Syringes and Bandages, specifically because these item types also don’t need an Entity if they aren’t in the players inventory and are often stored in large quantities (5,769 and 1,206 respectively in the above EU2 sample). Syringes in particular have been a performance bottleneck for the Industrial system due to the need to create and destroy an Entity every time the item is moved, so this change should have flow on server performance improvements there as well.

We think this change should reduce entity counts on the server by roughly 6-9% but we’ll be monitoring the results over time.

We received reports from several servers this month with Industrial performance issues. After investigating we found some extremely complex conveyor systems moving large amounts of Syringes as the culprit. The above changes to Entity counts will largely solve the issue, but I’ve also added a new convar (Server.industrialTransferStrictTimeLimits) to better handle time budgeting in these situations. While the Industrial system is time budgeted per frame (eg. Only process three conveyors per frame) it struggled if one conveyor took an excessive amount of time (eg. One conveyor takes 15x the allocated budget). 

This new convar will allow the conveyor system to stop half way through a transfer if it is taking too long. Crucially it will then resume the transfer from where it left off on the next tick, so the final results should be the same, they may just take longer in real time. From the players perspective, this may result in conveyors splitting things in unintuitive ways (eg. a conveyor splitting into three boxes might do 2 on the first tick, then the last one on the last tick) but it should eventually produce the same result. Therefore we’d recommend turning this on selectively if a server is experiencing Industrial performance issues.