Providing code example for Berdir's answer here to give you more information.

Read this article https://www.drupal.org/docs/7/api/batch-api/overview

and check the example module here to checkout the proper way of using the batch processing Drupal 8: https://github.com/GiantRobot/csvimport

you will then know how to alter you code to work.

cheers!

Providing code example for Berdir's answer here to give you more information.

Read this article https://www.drupal.org/docs/7/api/batch-api/overview

and check the example module here to checkout the proper way of using the batch processing Drupal 8: https://github.com/GiantRobot/csvimport

you will then know how to alter your code to work.

cheers!