Problem:
imuxsock begins to drop messages from pid due to rate-limiting
Solution:
vim /etc/rsyslog.conf
$SystemLogRateLimitInterval 60
$SystemLogRateLimitBurst 3000
/etc/init.d/rsyslog restart
Reference:
http://navyaijm.blog.51cto.com/4647068/1212042
http://www.rsyslog.com/tag/rate-limiting/