IO thread error : 1595 (Relay log write failure: could not queue event from master) Slave status :

           Last_IO_Errno: 1595
           Last_IO_Error: Relay log write failure: could not queue event from master
           Last_SQL_Errno: 0


from error log :

       [ERROR] Slave I/O for channel 'db12': Unexpected master's heartbeat data: heartbeat is not compatible with local info; the event's data: log_file_name toku10-bin.000063&lt;D1&gt; log_pos 97223067, Error_code: 1623
       [ERROR] Slave I/O for channel 'db12': Relay log write failure: could not queue event from master, Error_code: 1595



  I tried to restarting the slave_io thread for many times, still its same.
we need to keep on start io_thread whenever it stopped manually, hope its bug from percona 

I have simply written shell and scheduled the same  for every 10mins to check if io_thread is not running , start slave io_thread for channel 'db12';.   It's working as of now