Source file storage_costs.ml

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(* The model for read accesses is the following:

   cost(path_length, read_bytes) = 200_000 + 5000 * path_length + 2 * read_bytes
*)
let read_access ~path_length ~read_bytes =
  let base_cost = Z.of_int (200_000 + (5000 * path_length)) in
  Gas_limit_repr.atomic_step_cost
    (Z.add base_cost (Z.mul (Z.of_int 2) (Z.of_int read_bytes)))

(* The model for write accesses is the following:

   cost(written_bytes) = 200_000 + 4 * written_bytes
*)
let write_access ~written_bytes =
  Gas_limit_repr.atomic_step_cost
    (Z.add (Z.of_int 200_000) (Z.mul (Z.of_int 4) (Z.of_int written_bytes)))