Xtrabackup Error - SET SESSION lock_wait_timeout=31536000: MySQL server has gone away

While taking backup of our percona mysql DB, I’m getting this error:

SET SESSION lock_wait_timeout=31536000: MySQL server has gone away

The database is: Server version: 5.7.16-10-log Percona Server (GPL), Release ‘10’, Revision ‘a0c7d0d’

The Xtrabackup version that I use is

$ xtrabackup --version xtrabackup version 2.4.5 based on MySQL server 5.7.13 Linux (x86_64) (revision id: e41c0be)

The backup command that I’ve used is -

innobackupex /backuppath/

I use Ubuntu 16.04.1 LTS (GNU/Linux 4.4.0-59-generic x86_64)

Do you have any cron which kills long running queries in background e.g. pt-kill ? Can you please post full backup output along with my.cnf contents to check further. I also reported same bug earlier but it’s still not verified.