FESCo in https://fedorahosted.org/fesco/ticket/1311 decided to have syscall auditing disabled by default.
Please add something like this to /etc/audit/rules.d/audit.rules:
> # This suppresses syscall auditing for all tasks started
> # with this rule in effect. Remove it if you need syscall
> # auditing.
> -a task,never
audit-2.3.7-4.fc21 was built to address this.
*** Bug 1102868 has been marked as a duplicate of this bug. ***