PCU is short for Performance Cost Unit. It's the answer to the question "How do I find out which blocks have an impact on performance and are slowing my game down?"
Each block has a PCU value assigned that represents how much impact it has on game performace.
- If a type of block has a high performance impact, the devs assign it a high "PCU cost" to encourage players to use "costly" blocks only sparingly.
- If a type of block has a low performance impact, the devs give it a low "PCU cost", to let you know you can use them with less performance impact.
Also, an armor block on PC always costs 1 PCU, and on consoles (PlayStation and Xbox) it costs 2 PCU. Projected blocks also cost 1 PCU.
Why do I care about PCU?[]
If you use up your PCU, the HUD displays "PCU limit reached". The game won't let you build (or buy) any more grids before you remove some.
The PCU value is mostly relevant in multiplayer and console worlds: The goal of the PCU values is to give players a way to get a feeling for the performance impact of blocks and grids. This makes it easier for you to make smart (lower-cost) choices when building, and reminds you to keep the sim speed fast for everyone.
For example, large welder/grinder pits and asteroid-eating drill arrays slow down performance. If a server imposes a Block Limit so that each player can only build five drills, founding a faction with another player allows the two of you to build a mining ship with up to ten drills together.
Each multiplayer world has a global PCU limit, and each faction gets a part of it, and each player gets part of the PCU limit of their faction. This limit also keeps factions sizes fair and equal.
In an offline/singleplayer world on a recent PC, however, you can ignore PCU limits, until you build too big and get noticeable lag.
How much PCU am I using?[]
- Check your current grid's PCU usage on the grid's Info Screen.
- Check individual PCU usages of all your owned grids on your engineer's Info Screen.
- Check how much PCU is still free out of your total limit, press (G key) to open the Toolbar Config menu, and look at the numbers in the bottom right.
- Admins can sort the whole Entity List by PCU on the Admin Screen to identify grids that impact overall performance.
How can I decrease my PCU Usage?[]
These tips are for the sake of performance on multiplayer servers:
- Build compact modular ships with reusable ship cores and swappable tool attachments
- Don't buy more vehicles than needed from the Trading Outposts
- Build few Assemblers/Refineries with Upgrade Modules instead of several
- Grind down hacked wrecks
- Use the Info Screen (or Admin Screen) to delete lost wrecks that are still owned by you
How can I increase my PCU Limit?[]
By default, the max PCU is 100,000 on all platforms. In experimental mode it's 200,000[1] on consoles (Playstation 4 and Xbox) in Singleplayer, and it can be up to 500,000 on PC and PS5. On multiplayer servers, it could be lower, e.g. 20000. If you pay for a dedicated server, you can even remove the PCU limit for your game in experimental mode.
- You can set or disable the limits of your worlds in the World Settings under Block Limits before starting the game. (For Consoles use Space Engineers Beta it does have all current DLC’s)
- Multiplayer Admins can set global limits for everyone in the World Settings before starting the game. Admins can also give themselves the ability to build without Block Limits on the Admin Screen in-game.
- Players can trade PCU with other players on the same server. PCU is an extremely valuable second currency and worth more than Space credits: Consider that trading PCU means the seller can build and own fewer grids, and the buyer can build and own more. If you sell your PCU, you limit your ability to play. Selling unspent PCU basically only makes sense if you leave a server.