i have a problem of file reading .. i'm using javascript for reading excel file and making some data procedures in simple html app (just client - no server) .. it's going ok but when dealing with 50k rows and about 20 column and taking about 8 seconds to reading the data and store it in array .. i tried 100k rows also done but took longer but when i tried 500k i had this message "paused before potential out of memory crash" .my question is what this problem and how can i deal whit it? and what i have to do if i want to loop through huge data ! my work is dealing with huge data which my reach to 5 millions or may be 10m and i want to deal with them by converting csv or text to arrays ..what is the best way to do that without using server side and dbms?