heat.scaling.rolling_update module

heat.scaling.rolling_update.needs_update(targ_capacity, curr_capacity, num_up_to_date)

Return whether there are more batch updates to do.

Inputs are the target size for the group, the current size of the group, and the number of members that already have the latest definition.

heat.scaling.rolling_update.next_batch(targ_capacity, curr_capacity, num_up_to_date, batch_size, min_in_service)

Return details of the next batch in a batched update.

The result is a tuple containing the new size of the group and the number of members that may receive the new definition (by a combination of creating new members and updating existing ones).

Inputs are the target size for the group, the current size of the group, the number of members that already have the latest definition, the batch size, and the minimum number of members to keep in service during a rolling update.