You can run this query to check the innodb buffer pool size. It will give a suggestion on the actual size of innodb buffer pool that you must set based on the workload, data size, indexes etc. of your database.

    SELECT CEILING(Total_InnoDB_Bytes*1.6/POWER(1024,3)) RIBPS 
      (SELECT SUM(data_length+index_length) Total_InnoDB_Bytes
      FROM information_schema.tables
      WHERE ENGINE='InnoDB') A;

Use this query to check the usage of your innodb buffer pool

    SELECT (PagesData*PageSize)/POWER(1024,3) DataGB 
      (SELECT variable_value PagesData
      FROM performance_schema.global_status
      WHERE variable_name='Innodb_buffer_pool_pages_data') A,
      (SELECT variable_value PageSize
      FROM performance_schema.global_status
      WHERE variable_name='Innodb_page_size') B;