best practice for multiple batch update

i've created a function to update a local database
i'm using data from API and update local table with update batch
from table no 1 (around 8000 rows and 15 columns)
i got memory usage
64976504
and memory peak usage
144559440


after 3 table, memory usage
112891344
memory peak usage
152110656


i've increase memory limit to 256
i update the 3 table in 1 function, and theres 4 more table

is there any best practice to do batch update?
batch update in the model, and the function call it 3 times for the 3 table

thank you