ajax - PHP upload files to server script doesnt upload everything -

i'm using php , ajax upload files server, can upload txt files, images, docs, zips,pdf... uploaded pdf of size 15mb when tried upload txt size 14mb script crashed here code

<form id="form" action="db/upload.php" method="post" enctype="multipart/formdata">     <input type="file" name="filetoupload" id="file">\     <input type="submit" value="upload image" name="submit" id="">\ </form> 

javascript

//click event upload new file button $('#edit_window .file_container').on('submit', '#form', function(e) {      e.preventdefault();  //code uploading file //get file data       var file_data = $("#file").prop("files")[0];       var form_data = new formdata(this);       form_data.append('file', file_data);       form_data.append('link', id);        $.ajax({         type: 'post',         url: 'db/upload.php',         data:form_data,         cache: false,         contenttype: false,         processdata: false,         success: function (data) {             console.log(data);         //  $("#feedback").html(data);         }       });     }); 

php

<?php     session_start();      //prevent running script if no 1 logged in     if(!isset($_session["currentuser"]))             exit();      $link = $_post['link'];     $target_path = "../data/".$link."/";      $target_path = $target_path . basename( $_files[ 'filetoupload' ][ 'name' ] );      if ( move_uploaded_file( $_files[ 'filetoupload' ][ 'tmp_name' ] , $target_path ) ){        echo "upload complete!";     }      else {          echo "error uploading!";     }  ?>  

user.ini

upload_max_filesize = 40m post_max_size = 40m max_execution_time = 10000 max_input_time = 10000 

javascript output

<br /> <font size='1'><table class='xdebug-error xe-notice' dir='ltr' border='1' cellspacing='0' cellpadding='1'> <tr><th align='left' bgcolor='#f57900' colspan="5"><span style='background-color: #cc0000; color: #fce94f; font-size: x-large;'>( ! )</span> notice: undefined index: filetoupload in c:\wamp\www\elmar\db\upload.php on line <i>8</i></th></tr> <tr><th align='left' bgcolor='#e9b96e' colspan='5'>call stack</th></tr> <tr><th align='center' bgcolor='#eeeeec'>#</th><th align='left' bgcolor='#eeeeec'>time</th><th align='left' bgcolor='#eeeeec'>memory</th><th align='left' bgcolor='#eeeeec'>function</th><th align='left' bgcolor='#eeeeec'>location</th></tr> <tr><td bgcolor='#eeeeec' align='center'>1</td><td bgcolor='#eeeeec' align='center'>0.0020</td><td bgcolor='#eeeeec' align='right'>245888</td><td bgcolor='#eeeeec'>{main}(  )</td><td title='c:\wamp\www\elmar\db\upload.php' bgcolor='#eeeeec'>..\upload.php<b>:</b>0</td></tr> </table></font>