Hi, this bug happened again. This time I have more context: it occurred during the execution of the acct cron job:
Apr 12 07:35:10 irancy anacron[7284]: Updated timestamp for job `cron.daily' to 2017-04-12 Apr 12 07:35:10 irancy nullmailer[7282]: smtp: Succeeded: 250 OK id=1cyAvu-00020k-FW Apr 12 07:35:10 irancy nullmailer[18624]: Sent file. Apr 12 07:35:10 irancy nullmailer[18624]: Delivery complete, 0 message(s) remain. Apr 12 07:35:12 irancy systemd[1]: Stopping LSB: process and login accounting... Apr 12 07:35:12 irancy acct[7346]: Turning off process accounting. Apr 12 07:35:12 irancy acct[7346]: Done.. Apr 12 07:35:12 irancy systemd[1]: Stopped LSB: process and login accounting. Apr 12 07:35:12 irancy systemd[1]: Starting LSB: process and login accounting... Apr 12 07:35:12 irancy acct[7368]: Turning on process accounting, file set to '/var/log/account/pacct'. Apr 12 07:35:12 irancy kernel: NOHZ: local_softirq_pending 80 Apr 12 07:35:12 irancy kernel: NOHZ: local_softirq_pending 80 Apr 12 07:35:12 irancy kernel: NOHZ: local_softirq_pending 80 Apr 12 07:35:12 irancy kernel: NOHZ: local_softirq_pending 80 Apr 12 07:35:12 irancy kernel: NOHZ: local_softirq_pending 80 Apr 12 07:35:12 irancy kernel: NOHZ: local_softirq_pending 80 Apr 12 07:35:12 irancy kernel: NOHZ: local_softirq_pending 80 Apr 12 07:35:12 irancy kernel: Process accounting resumed Apr 12 07:35:12 irancy acct[7368]: Done.. Apr 12 07:35:12 irancy systemd[1]: Started LSB: process and login accounting. -- Laurent.