Actual PROPER way to instantiate many entities at once?

Hello,

The documentation, tutorials, and my searches all give me contradictory information regarding the spawning of many entities while taking advantage of jobs and threads. I'm confused.

For simplicity, let's say that, for whatever reason, I want to instantiate 50000 entities at once. I want to do this in pure ECS: not a single MonoBehavior involved or weird hybrid authoring at all. What's the most performant/correct way to do this as of today?

Things I've heard:

• You use World.Active.EntityManager.CreateEntity(). But this can be only called from the main thread anyway.
• You use EntityCommandBuffer to queue the creation of the entities. It will run at the end of the frame. But then again it feels pointless, because the actual creation of the entities will simply be queued to run "one-by-one" in the main thread.
• You use EntityCommandBuffer with EntityQuery (seen here). I don't understand how this would improve things since we still depend on queuing the instantiating of the entities and running them one-by-one in the main thread.

I've seen some other approaches but frankly, none of them make total sense to me. I can get them all working, but something feels wrong.

What am I missing? Is entity composition and instantiation simply supposed to be done in the main thread, and I'm just overthinking this?

I appreciate your help.

 

From what I've heard using CreateEntity() with the NativeArray overload is still the fastest way.

 

I am not a pro, but creating entities(structral change) causes chunks to be re calculated, thats why it is being done in main thread.

 

Batch operations on EntityManager by far the fastest way to create lots of entities or set lots of components - order of magnitude faster than ECB

 

Thank you. I really appreciate everybody's help.