SQLSTATE[HY000]: General error: 1205 Lock wait timeout exceeded; try restarting transaction (Drush Cache Rebuild)

Problem with Drupal (after "drush cr"):

#drush cr

In ExceptionHandler.php line 56:
                                                                                                                                                                           
  SQLSTATE[HY000]: General error: 1205 Lock wait timeout exceeded; try restarting transaction: DELETE FROM "cache_discovery"                                               
  WHERE "cid" IN (:db_condition_placeholder_0, :db_condition_placeholder_1, :db_condition_placeholder_2, :db_condition_placeholder_3, :db_condition_placeholder_4); Array  
  (                                                                                                                                                                        
      [:db_condition_placeholder_0] => element_info_build:bartik                                                                                                           
      [:db_condition_placeholder_1] => element_info_build:seven                                                                                                            
      [:db_condition_placeholder_2] => element_info_build:bootstrap                                                                                                        
      [:db_condition_placeholder_3] => element_info_build:mydbname1                                                                                                         
      [:db_condition_placeholder_4] => element_info_build:claro                                                                                                            
  )                                                                                                                                                                        
                                                                                                                                                                           

In StatementWrapperIterator.php line 113:
                                                                                               
  SQLSTATE[HY000]: General error: 1205 Lock wait timeout exceeded; try restarting transaction  
                                                                                               

Solution?