Since the new migration of log files management from syslogd to aslmanager it is possible to encounter some problems regarding the high CPU usage by aslmanager process. One of the solution is to restart the aslmanager indexing by moving the logs in a temporary directory and restarting the syslogd/aslmanager service. Here are the commands:
Stopping the syslogd and aslmanager service:
sudo launchctl stop com.apple.syslogd
sudo launchctl stop com.apple.aslmanager
Moving the logs in a backup directory:
mkdir -p ~/Desktop/temp/
sudo mv /var/log/asl/* ~/Desktop/temp/
Restarting the syslogd service (aslmanager service will be started automatically by syslogd service when needed):
sudo launchctl start com.apple.syslogd