Question about SystemParam

[MuongKimhong]

Consider this as a noob question!

Let say I have this struct.

#[derive(SystemParam)]
struct Config<'w, 's> {
    query_a: Query<'w, 's, ........>, // about 10 - 15 components
    query_b: Query<'w, 's, ........>,
    query_c: Query<'w, 's, ........>,
    .
    .
    query_n: Query<'w, 's, ........>,
    mut my_resource: ResMut<'w, ConfigData>
}

impl<'w, 's> Config<'w, 's> {
    fn work_with_query_a(&mut self) {
        // do some iterations and mutations
    }
}

From bevy documentation:
Creating a Query is a low-cost constant operation. Iterating it, on the other hand, fetches data from the world and generates items, which can have a significant computational cost.

My question:
"Does it mean in my systems, having Config as system param will not hurt the performance as long as I don't call any of its methods which iterate thru the queries like work_with_query_a()?"

Please advise, thanks!

[Henauxg]

As you have linked from the Query documentation, creating the Query should not have the performance cost associated with running it.
However, there is still a way that these queries may hurt performance just by their declaration: when using the multi-thread executor (default), these queries may prevent other systems querying some of the same Components from running in parallel with your system using this SystemParam (depending on the declared Components mutability). So if you rely highly on systems parallelism, this might something to be aware of.

[MuongKimhong]

Thanks