You can specify the --compress option to compress the backup:
shell> mydumper -u root --password=<password> -B employees -T employees -t 8 --trx-consistency-only --compress --outputdir /backups/employees_compress
shell> ls -lhtr /backups/employees_compresstotal 5.3M-rw-r--r-- 1 root root 91 Aug 13 11:01 employees-schema-create.sql.gz-rw-r--r-- 1 root root 263 Aug 13 11:01 employees.employees-schema.sql.gz-rw-r--r-- 1 root root 75 Aug 13 11:01 metadata-rw-r--r-- 1 root root 5.3M Aug 13 11:01 employees.employees.sql.gz
