Parsing an excel with more than 12000 lines in PHP with PHPExcel -

i have trouble when try upload , parse through phpexcel library xlsx file 12500 rows , 20 columns whole process takes ten minutes end, querys , validations. upload works fine, when starts parse excel file rows excel library fails. have divided 2 files big file, works fine.

is posible parse file of more 12000 lines , 20 columns in phpexcel, without fail?

and i'd suggestion.

is more fast , light parse csv file(i think so) parse excel file, when talking many lines?

the browsers die minute 3 of execution, process in server continues. there anyway browser doesn't reset connection? , why process continues in server , browser dies?

i'm thinking pass process ajax avoid point, think of that?

what's better way parse type of files number of lines?

thank much!