要改php.ini，基本是改這幾項：
max_execution_time = 30
max_input_time = 60
memory_limit = 8m
upload_max_filesize=8m

php.conf發現內容如下：
#
# php is an html-embedded scripting language which attempts to make it
# easy for developers to write dynamically generated webpages.
#

loadmodule php4_module modules/libphp4.so

addtype application/x-httpd-php php .php3

#
# cause the php interpreter handle files with a .php extension.
#

setoutputfilter php
setinputfilter php
limitrequestbody 524288


#
# add index.php to the list of files that will be served as directory
# indexes.
#
directoryindex index.php

看到那個524288嗎，換算下就是512k。把它改成52428800，reload apache。經測試，可以上傳幾十兆的文件，問題解決。