How is the ram reallocated when a table is modified?

Question

if i do :

//usera creates a new row in the table
table.emplace(usera, [&](auto &s) {
   s.name = “Alice”;
});

and then do:

//userb then modifies the same row that usera created
table.modify(reference_to_tablea, userb, [&](auto &s){
   s.name = “Bob”;
};

is the ram fee split between userb and usera or does userb pick up the entire ram fee and usera gets their ram back?

Answer 1

userb picks up the entire ram cost. usera gets their ram back:

reference here: https://github.com/EOSIO/eos/blob/v1.0.8/libraries/chain/apply_context.cpp#L459