Hello, CTO of Terrateam here, the creators of Stategraph.
As you said, the common practice is to use locks on state to guarantee that operations don't step on each other. This works, however the cost is that if it takes 5 minutes to perform an operation, only one person can be doing an operation at a time, so if 5 devs are modifying infrastructure, the last one has to wait 25 minutes just to get back the plan, even if those 5 people are not changing overlapping resources in the state.
The way that most people deal with this is they take their infrastructure and break it up across multiple root modules, and then when those root modules, break it up again, etc.
Stategraph is solving the problem of getting all of the performance benefits of breaking up your root modules without breaking up your root modules. It dynamically determines which resources each of those 5 devs are operation on and, if the resources do not overlap, can run them in parallel.
That means Stategraph is manipulating state in a bit more sophisticated way than standard Terraform/Tofu, and we need to be careful we don't get it wrong.
As you said, the common practice is to use locks on state to guarantee that operations don't step on each other. This works, however the cost is that if it takes 5 minutes to perform an operation, only one person can be doing an operation at a time, so if 5 devs are modifying infrastructure, the last one has to wait 25 minutes just to get back the plan, even if those 5 people are not changing overlapping resources in the state.
The way that most people deal with this is they take their infrastructure and break it up across multiple root modules, and then when those root modules, break it up again, etc.
Stategraph is solving the problem of getting all of the performance benefits of breaking up your root modules without breaking up your root modules. It dynamically determines which resources each of those 5 devs are operation on and, if the resources do not overlap, can run them in parallel.
That means Stategraph is manipulating state in a bit more sophisticated way than standard Terraform/Tofu, and we need to be careful we don't get it wrong.