Been trying to figure this out for a while now but it appears jenkins is not using the slaves as expected.

I have 2 Suse Slave nodes for my jenkins master assigned to a tag "OnPrem"

all builds use the restrict where this build can be run option and attempt to use the OnPrem tag.

each slave has 10 executor threads.

now I expected jenkins to balance between all slave nodes in round robbin
eg; job a on node 1 job b on node 2 job c on node 3 and this is not case.

So I thought oh maybe it balances by load and places the job on the less utilized node, This again does not appear to be the case.

finally ( getting desperate) I suspected it may balance via exector threads in round robbin although this would be strange and use all 10 executor threads on node 1 before using node 2, This is also not the case.

I cant seem to find a configuration option anywhere.
The main point of the post is to understand how it balances is anyone aware of how jenkins treats slaves and how it chooses executor threads for jobs. Cant seem to find documentation on this.