Server sends mysql has gone away error

Question

I use comet in my website.. The long polling script returns "Mysql has gone away" error often...

I have used mysqli extension (object-oriented) to connect php with mysql database

even php *mysqli -> ping()* method doesn't fix this problem.

The best part of this is the error did not occur for two months i was using this website with comet But now it occurres....

Tips: I changed mysql database's collation to utfmb4_unicode_ci and charset to utbmb4

How can i fix this?

Answer 1

You need to check below thinks in my.cnf

check that wait_timeout mysql variable in your my.cnf configuration file is large enough.

Also check max_allowed_packet

 set max_allowed_packet = 128M, 

then restart your MySQL server