Sometimes on our local dev mysql5.6 instance, if we import large databases (8 gig of .sql file) we get 'MySQL server gone away'.
We collected these settings on the internet, which seem to solve it:
max_allowed_packet = 256M
innodb_lock_wait_timeout = 3600
net_read_timeout = 3600
net_write_timeout = 3600
wait_timeout = 3600
innodb_log_file_size=500M
innodb_log_buffer_size = 800M