TO build on Flog's example - I am going to leave it generic because Shares work the same for all resources -
Between the two reource pools and two VMs you will a total pool of 22000 Shares - when there is contention between all four the resource will be split as follows - the two reourse pools each will be getting 10000/22000 of the available resource and the two VMs each will be getting 1000/22000 of the available resource -
Key thing to remember is shared only come into play when there is contention -